Paul Drake, seated at his office desk, a cup of black coffee in front of him, an electric percolator plugged into a socket and bubbling away, said, “How do you two do it? I’ve got my eyes propped open with toothpicks.”

Mason said, “Excessive sleep is a habit, Paul. You must learn to control it. It will grow on you until you’ll find you’ll need two and three hours’ sleep a night if you aren’t careful.”

“Well,” Paul said, “I haven’t got to that point yet. An hour or an hour and a half would seem like a swell break. Two hours would leave me doped. I suppose you two have been skylarking around in night clubs and just couldn’t get here sooner because the orchestra didn’t quit.”

“That’s right,” Della Street said, holding out her arms straight from the shoulders and moving around the office in a waltz as she hummed a tune. “It was perfectly divine, Paul!”

Drake grinned and said, “Nuts to you. You’re not kidding me any. You’ve been out committing a murder somewhere. Whose body have you turned up now?”

Della Street ceased waltzing, said scornfully, “That’s the trouble with you, you have no romance. You’ve let life get you into a business rut, and just when I was beginning to tingle you start bringing up murders! Now the boss will talk shop — and we were having such a good time!”

Drake said, “I’ve been having a great time stalling Mrs. Gentrie for you folks. Tragg arrested her boy tonight. She’s frantic. She called me around midnight I told her you’d be in here around half past two or three o’clock. She said she’d wait up for you. I said I didn’t think you’d see her tonight, but she said she’d wait up anyway.”

Mason said, “I might see her, at that.”

“She doesn’t know anything new, Perry. She’s just a frantic mother, trying to save her boy.”

Mason slid over on the edge of Drake’s desk. “Got any more coffee cups, Paul?”

Drake opened a drawer, pulled out some agateware mugs and said, “I can give you a couple of these. It’s all I ever use.”

Della Street said, “Don’t talk so much. Just pour.”

Drake turned the spigot on the percolator, drew out two big cups of golden brown coffee. “If you want cream or sugar,” he said, “you get neither. This is a business office.” He grinned.

Mason said, “What about Rodney Wenston, Paul?”

“I was trying to get you to tell you that he went to San Francisco right after Lieutenant Tragg’s visit. This time they must have known my man was watching, because Karr’s feet never touched the ground. They lifted him out of a car and into the plane as though he’d been a baby.”

“What was Wenston doing before that?”

“He’s been around off and on all day.”

“Could he possibly have gone to San Francisco and back before he made that trip in the evening?” Mason asked.

Drake consulted his memo and said, “Not unless he went real early in the morning. Of course, we weren’t keeping him shadowed. We’ve made a general check-up. He started for town about noon. That is, the caretaker at his place said that’s when he left, and the man at the service station at the fork of the road, where he usually buys his gas, said he went past about one o’clock; but didn’t stop to buy any gas.”

“Driving his car?”

“Uh huh. Then he was in your office around three o’clock, I guess, wasn’t it?”

Mason nodded. “Somewhere around there.”

“Two-fifty-five he came in,” Della Street said.

Drake looked at her. “You keep a memo of the time everyone comes in?”

“And when they leave. How do you suppose I can see that Perry charges for his time?”

Drake said, “It’s a good idea. I guess I’ll have my switchboard operator start doing the same thing. I should get double wages for overtime, shouldn’t I, Perry?”

“You should,” Mason said, “but I don’t think you can make it stick. What about Delman Steele?”

“I don’t get that bird,” Drake said. “He’s supposed to have a job in an architect’s office, but when I checked up on him, it didn’t pan out.”

Mason gave Della a swift glance. “How do you mean?” he asked Paul.

“Well, he hangs around the office all right, but the architect says that Steele doesn’t actually have any connection with the business. He rents desk room and comes and goes as he pleases.”

“When was he in the office yesterday?” Mason asked.

“Came in about nine in the morning as usual, left about ten, and came back about two. He was in until around three o’clock, and then left for the evening. Funny thing, Perry. He has that room at Gentrie’s house. It has an outside entrance so he can come and go as he pleases, but he’s made himself one of the family and spends quite a bit of time there. Mrs. Gentrie thinks he’s lonely and...”

“I know all that,” Mason said. “What time did he get in last night?”

“I don’t know,” Drake said. “I got your call too late to ring him up on some excuse. In fact, she rather pointedly mentioned to one of my men that he didn’t have the privilege of using their telephone. I found out about the arrangement in the architect’s office more or less by chance. We didn’t want to seem to be investigating him because you said to handle it in such a way no one would get the least bit suspicious. So we’d always taken it for granted that he was an architect. His name’s on the door of the architect’s office down in the lower righthand corner, and he certainly gave the Gentries to understand he was an architect. But around cocktail time this afternoon one of my men got acquainted with the architect and started asking casual questions. That’s when he found out about Steele. Mrs. Gentrie may know something, in case you do go out there.”

Mason said, “Well, I guess there’s nothing to do tonight except sleep on it.”

“Tonight!” Drake said, looking at his watch. “It’s dam near daylight.”

“It’s always night until it’s daylight,” Mason said. “Go ahead. Finish your coffee, Della. Let’s go.”

Della Street tilted up her coffee cup. “Going to see Mrs. Gentrie?” she asked.

Mason nodded.

“How you folks do work,” Drake said. “Personally, I’m going to get some shuteye.”

Mason started for the door, then abruptly turned, stood with his hands pushed down in his pocket looking at Paul Drake with troubled eyes. “Paul,” he said, “you’ve got to do something.”

“Not until I get some sleep,” Drake protested.

Mason simply kept looking at him.

“What is it?” Drake asked, at length.

“You’ve got to get a confession from Karr.”

“A confession!” Drake exclaimed.

Mason nodded.

“I don’t get you.”

Mason said, “I’ll give you the high spots. Hocksley wasn’t killed. He was only wounded. I want to find out who shot him and why.”

“How do you know he was only wounded?”

“Because I’ve seen him.”

“You’ve seen him!” Drake echoed, startled.

“Yes.”

“Where?”

“In the Parker Memorial Hospital in San Francisco.”

“What did he say?”

“He didn’t say anything. He had evidently been given a hypo. He’s going to live, but the doctor’s trying to keep him out of circulation.”

“How did he get to San Francisco?”

“Wenston flew him up.”

“Wenston! Then he’s double-crossing Karr...”

Mason interrupted Drake to say, “No, he isn’t. Karr and Hocksley are one and the same person.”

Drake pushed back his chair and got to his feet. “Perhaps I’ve had too much coffee, Perry, or perhaps you have. One of us certainly is cockeyed. Hocksley is a red-headed man with a limp who...”

Mason said, “I’ll put it this way. The one who rented the apartment was Johns Blaine dressed up with a red wig and purposely walking with a limp. In renting the apartment, however, under the name of Hocksley, he was acting as Karr’s agent. Don’t think for a minute that a man of Karr’s shrewdness would establish a hide-out in a two-flat building without controlling the lower as well as the upper flat.”

“That sounds reasonable,” Drake admitted, “but what makes you think Karr’s flat is a hide-out?”

“Karr’s engaged in getting munitions over to China through a leak in the blockade. Naturally, he doesn’t want publicity.”

“Then the safe in the lower flat belongs to Karr?”

“Yes.”

“Why didn’t he keep that safe in the upper flat?”

“Probably because Johns Blaine keeps an eye on the safe, and sleeps in the lower flat.”

“Then this housekeeper, Sarah Perlin, must have known.”

“Of course.”

“And Opal Sunley.”

“Not necessarily,” Mason said. “She may or may not have known. It doesn’t make a great deal of difference. The housekeeper lived there. Opal Sunley came by the day.”

“But you say Hocksley was wounded. Then if Hocksley is Karr, Karr must have a bullet hole...”

“In his leg,” Mason interpolated. “That’s why he’s keeping his legs covered, so the bandage won’t show.”

“He doesn’t have arthritis?”

“Probably, but not as bad as he wants us to believe now.”

“Wait a minute, Perry,” Drake said. “A doctor wouldn’t treat a bullet wound unless he reported it to the police.”

“That’s right,” Mason agreed, smiling.

“I don’t get you.”

“Karr,” Mason said, “is a man of varied activities. He’s very resourceful. Evidently, he carries on most of his activities under other roofs and under other names. Here in Hollywood, he’s Robindale E. Hocksley when it comes to transacting business. Up in San Francisco, he’s Carr Luceman, residing at thirteen-o-nine Delington Avenue.”

“I don’t give a damn how many names he’s got, Perry. He still can’t get a gunshot wound treated without...”

“Without making some explanation which would satisfy the doctor and the police,” Mason said. “As Elston Karr who had the flat above a flat where a murder had been committed, he naturally couldn’t have made any explanation in Los Angeles; but as Carr Luceman, living in San Francisco in a neighborhood where there hadn’t been any murders, he had no difficulty in thinking up a story which would hold water with the police.”

“What do you want me to do?”

“Make him admit the whole business. I’m hardly in a position to put the screws on him. You are.”

“Where is he now?”

“In a hospital.”

“Didn’t the doctor send him to a hospital the first time he saw him?”

“Apparently not. It was a wound that wasn’t particularly serious unless complications set in. The doctor probably advised him to keep quiet and call him in the event any unusual symptoms developed.”

“Just what do you want me to get?” Drake asked.

“Dig up any information you can, find out his version of what happened the night of the shooting.”

Drake said, “Won’t I get into trouble, keeping this information from the police?”

“You haven’t any information, have you?”

“You’ve told me a lot of stuff.”

Mason grinned. “You don’t think that it’s incumbent on you to run to the police every time some lawyer gives you a goofy theory of a case, do you?”

Drake hesitated for a moment, then said, “Well... well, no.”

Mason winked at him and said, “In all probability, it’s just a crazy theory I have, but here’s a newspaper clipping giving an account of how Carr Luceman happened to shoot himself in San Francisco. I’d like to have you make an investigation of the circumstances.”

Drake said, “When do I leave?”

“Charter a plane. You can grab forty winks on the plane.”

“Oh, not forty winks,” Drake protested sarcastically. “Twenty would be all I could possibly use. I don’t want to start getting too much sleep! Does Wenston know about this?”

“He must.”

“About the bullet wound?”

“Probably. He flew Karr up there this afternoon. Karr was beginning to run a fever when I saw him last. His skin was dry and parched, and his face flushed.”

“Who knows about what happened the night of the shooting?” Drake asked. “Anyone besides Karr?”

“Yes,” Mason said. “One person anyway.”

“Who?”

Mason grinned. “The one who pulled the trigger.”

Drake reached for the telephone, said to the switchboard operator, his voice low-pitched from sheer physical fatigue, “Get me the airport. I want to rent a good cabin plane for a rush trip to San Francisco.”

Mason nodded to Della Street. “Okay, Della, let’s go tackle the other end of this case.”

Driving out to Mrs. Gentrie’s, Mason said, “I should have had Steele spotted a long time ago.”

“I don’t see how.”

“Simple,” Mason said. “Remember when we were talking over the case, I said that the person in the house who was getting the messages must have been someone who had easy access to the dictionary, and who, for some reason, couldn’t very well be called to the telephone. Remember, Mrs. Gentrie told me right at the start that Steele had his room and was treated as one of the family, except that he didn’t have the privilege of using the telephone. There were too many people using it already. She has three children, all of whom are at the age of making dates of one kind or another. Whenever the phone rings, there’s a mad scramble to see which one gets there first. When anyone wants to call out, one of the children is nearly always using the phone. Remember what she said.”

Della nodded.

“Here I was,” Mason said whimsically, “looking for someone who couldn’t use the telephone, and I was thinking in terms of some physical handicap, such as a man who was deaf or crippled. It never occurred to me to consider the simplest possible solution — a man who was living at a place where he didn’t have the privilege of the telephone, yet who couldn’t put in a phone of his own without attracting too much attention.”

“But why was Steele killed, if he was the one for whom the messages were intended?”

Mason said, “We’re evidently dealing with the after-math of an old feud. There’s no other explanation which occurs to me at the moment. Of course, we haven’t all of the facts as yet.”

“Then Karr must have killed him.”

“Karr’s time’s too well accounted for,” Mason said. “And Wenston is out of it. Steele must have been killed at least two hours before we got there. There’s no question but what Karr’s been and still is a very sick man. That bullet hole in his leg, the loss of blood, the shot, and the general strain of events must have taken a lot out of him. He isn’t physically robust. Then, in addition, he’s had that arthritis in his legs. Evidently, he could walk, but it was a slow and painful process. We can leave him out so far as Steele is concerned.”

“You think Karr went downstairs the night of the shooting?”

Mason said, “That’s the only logical deduction. The burglar alarm was placed where he could hear it. He admits that he did hear it. He must have got up and walked slowly downstairs. He surprised someone at the safe, and got shot.”

“Do you suppose Steele got the message you left in the tin before — before he was killed?”

Mason said, “I don’t know. His death is going to complicate things somewhat.”

“How do you mean?”

“There are two persons involved. One of them is the person who sent the message, and the other the person who received it. Now, if we assume that Steele is the person who was receiving the messages, the question arises, Who was sending them? Let’s suppose, for the sake of the argument, that it was Sarah Perlin. Steele sees a can placed on the shelf after Sarah Perlin’s death. Therefore, he knows it must be a trap. For that reason, he won’t touch the can. On the other hand, if Sarah Perlin wasn’t the one who was sending the messages, Steele — conceding that he’s the person who was receiving them — would undoubtedly have grabbed that decoy can the first chance he had.”

Della said, “I’m getting all topsy-turvy. I thought the person who had sent the message, and the person for whom it had been intended were the murderers. It looks now as though they were the victims. Now, what are we going to do?”

Mason said, “While we’re at the Gentrie residence, I’ll make some excuse to get down in the cellar. If the can’s still there, it will be significant.”

Della Street’s voice was filled with conviction as she declared, “The can will still be there. It’s dead open and shut. Mrs. Perlin must have been the one who was sending the messages, and Steele the one who was receiving them. They’ve both been killed. Even if we didn’t have an iron-clad case against those two, their deaths would prove it. You can see what happened. Mrs. Perlin was a spy. She was reporting to Steele. That was the reason Karr’s attempt to trap the real Hocksley failed.

“Karr took the bullet in his leg, but that was all he needed to show him what was going on. With truly Oriental cunning, he tracked down the two persons who were responsible, and killed them.”

Mason said, “There’s another angle that puzzles me. What became of the real Hocksley?”

“The one who was in China?”

“Yes.”

“Don’t you suppose he’s dead?”

“There’s nothing to indicate it. Karr must have had some reason for taking that lower apartment under the name of Hocksley. He could have used any one of a thousand fictitious names, but instead of doing so, he has Johns Blaine make himself up so he looks like Hocksley, and then takes the name of Hocksley. That must be significant.”

“Gosh, Chief, I wonder if Hocksley enters into the picture. After all, if he’s anywhere around and saw his name in the papers — well, you can see what would happen. Karr has managed to hide his identity by taking the flat under the name of Rodney Wenston, but this case is getting a lot of newspaper publicity. If Hocksley is anywhere in the country, he’ll see his name in the papers and — well, don’t you see? It makes sort of a sieve that sifts out everything except one particular-sized article. Karr has hidden himself from everyone except Hocksley, but Hocksley will read about what happened and come to that apartment just as certain as — but what am I doing, rattling along this way? Paul Drake’s coffee must have given me this talking jag.”

Mason was frowning thoughtfully. He said, “Go ahead, Della, keep on talking. You’re doing fine.”

She shook her head. “I absolutely refuse to solve cases for you. It’s a violation of my contract with the union.”

“You’re not trying to solve the cases,” Mason said. “You’re simply giving me ideas.”

“You don’t need anyone to give you ideas,” she said. “Or do you?”

They laughed.

Abruptly, she settled down against his shoulder with a little wriggling motion. “I’m getting my wires crossed,” she admitted. “In order to get anywhere in this world, a woman is supposed to be feminine and leave the thinking to the males. They like it better that way.”

“You must have been taking lessons,” Mason said.

She yawned sleepily. “I have. It’s a swell book. Sex Appeal for Secretaries, in two volumes. It says a well-trained secretary never argues with her boss.”

“Can’t a boss argue with his secretary?”

“It takes two to make an argument. Go ahead, Chief, and solve your mysteries. I’m supposed to stand by and hold your coat. Here I was, forgetting myself and trying to put it on, and — somehow, I don’t think it fits.”

The rambling frame structure of the Gentrie residence was dark and somber, save for the dining room and kitchen, which were ablaze with light. Mason parked his car and climbed the long flight of stairs which led up from the street to the porch level.

“Remember now,” he cautioned Della Street, “not to show too much interest in that can.”

He tapped gently on the door with his knuckles.

They heard the sound of quick steps from the inside of the house, then Mrs. Gentrie flung open the door. She pressed her finger to her lips for silence. “Please don’t make any more noise than possible,” she said. “I would prefer not to have my sister-in-law in on this. She’s never been very tolerant about the children.”

Mason nodded.

“Come in,” she invited.

They filed into the house, and Mrs. Gentrie escorted them through the living room into the dining room. “I hate to ask you to talk in here,” she said in a low whisper, “but the living room is right under Rebecca’s bedroom. She wants to know everything that’s going on, and very definitely she isn’t fair to Junior. What’s more, that police lieutenant has been flattering her with a little attention, and it’s turned her head. If we talked over anything where she could hear it, Lieutenant Tragg would know all about it before noon. He flatters her, and she thinks he’s simply wonderful.”

“What did she say when she knew Junior had been arrested?” Mason asked in a low voice.

“She doesn’t know yet. I just didn’t feel up to telling her. I didn’t know when you’d come, and I knew that she’d sit up and keep up an interminable chatter.”

“What happened?” Mason asked. “Tell me in exact detail.”

Mrs. Gentrie said, “Well, of course, I expected it. Lieutenant Tragg dropped in about dinner time. And Junior wasn’t here. His father said Junior had complained of not feeling well about three o’clock in the afternoon, and he’d told the boy to go on home. Naturally, he was surprised and irritated to find Junior wasn’t here.”

Mason nodded.

“What did Tragg say to that?”

“I think Lieutenant Tragg was very angry — not with us exactly, but with himself. He thought he should have done something about Junior earlier. He put men on watch at the house, and instructed the telephone company to disconnect our telephone. We were held here during the evening as virtual prisoners. Of course, the other children had to learn about it.”

“Was Steele here?”

“No. He’s out several nights each week. I just can’t size that boy up. He seems lonely. He’s certainly attractive enough, but I don’t think he has any girl friends. He just seems to enjoy sitting around with the family.”

“How about Rebecca?” Mason asked.

“Fortunately, she didn’t come in until after Tragg had left. There is only one thing she really cares for besides crossword puzzles and photography, and that’s opera. She had a crossword-club dinner meeting, and it’s also her opera night.”

“What time did Junior finally arrive?”

“Almost eleven o’clock.”

“Did Tragg ask him any questions?”

“No. He took him into custody. Then he took away the men who had been watching the place, and a short time after that the telephone rang. It was the telephone company to say that our telephone had been temporarily out of order, that service was now restored. I called your office right away. Of course, no one answered. I didn’t think anyone would. Then I called Mr. Drake’s agency, and it must have been nearly midnight when I got in touch with him. He told me he thought he’d be in touch with you later on, and if I’d wait up he’d pass the message on.”

Mason said, “But if Tragg had men watching the house, Steele must have been stopped when he came in.”

She said, “Yes — that’s right, if he came in before Junior.”

Mason said, “I’d like to know just where Tragg had his men stationed, and whether those men knew Steele by sight. I wonder if we could wake Steele up to ask him a couple of questions.”

“Oh, I’d hesitate to do that,” Mrs. Gentrie said. “After all, you know, he’s a roomer.”

“There’s a door which leads to his room from here?”

She pointed toward a door which opened from the hallway leading from the dining room to the foot of the stairs. “He has his own private exit and his own bath,” she said. “We rent him the room, then, of course, he can come in here whenever he wants to. We try to treat our roomers as one of the family — except on telephone service. We have so many telephone calls, because of the children and...”

“I understand,” Mason said. “How about knocking on his door?”

“Oh, I wouldn’t,” Mrs. Gentrie said.

Mason said thoughtfully, “Well, after all, it’s rather important.”

Mrs. Gentrie said, “I’d rather you’d just take a peek inside. I’d prefer almost anything than to have Rebecca come down now with all of her questions and — you know, if she got the idea I knew Junior wasn’t in his room when that shot was fired she’d tell lieutenant Tragg. Oh, Mr. Mason, please tell me that Junior didn’t do it. That’s the thing that’s been torturing me. You know how it is with a young boy, when he becomes infatuated with an older woman with more worldly experience. If she’s inclined to play him along, she can make a terrible fool of him. And all through this thing, Junior has acted so queerly. He just drew himself up very straight and erect and white-faced when Lieutenant Tragg placed him under arrest. He didn’t say a word.”

Mason said, “I want to see if Steele keeps his door locked. That may have some bearing on the whole thing.”

He crossed the dining room to the hallway, turned the knob of the door gently. It swung open on well-oiled, noiseless hinges. He looked inside, swung the door wider open so that light from the dining room illuminated the bedroom.

“There’s no one here,” he said.

Mrs. Gentrie got to her feet. “Why, good heavens, it’s well after three o’clock. Of course, he does stay out rather late at times, but I never knew him to be as late as this.”

Mason said, “However, because he has his own private exit and entrance, he could come and go very easily without you hearing him, couldn’t he?”

She said, “Yes, I suppose so.”

Mason swung the door tentatively back and forth. “These hinges,” he said, “seem to have been freshly oiled.”

“Well, I declare to goodness,” Mrs. Gentrie observed, examining the hinges. “They certainly have!”

“ You didn’t oil them?”

She shook her head.

“Could they have been oiled for some time without you noticing it?”

“Rebecca does the dusting and cleaning up in here. She certainly should have noticed — but she didn’t say anything. Hester cleans and dusts the outside. She might not have noticed. She isn’t particularly perceptive.”

Mason said, “Steele was in an admirable position then to leave this room, cross the kitchen, go down the cellar stairs, cross through the garage, and go over to the flat next door.”

“Why... why, I guess he could have if he’d wanted to.”

Mason went on, “There’s a door leading from the cellar into the garage, then a door from the garage leading into the yard, and a few feet beyond that a side door to Hocksley’s flat. Is that right?”

She nodded and said, “But I can’t understand... Surely, Mr. Mason...”

Mason said, “Let’s just step inside this room for a moment. I want to look around a bit.”

“I’m afraid he wouldn’t like it if he should come in.”

“I think I can take the responsibility for that,” Mason said. “It’s rather important to find out why Mr. Steele isn’t in now, why the hinges on his door have been oiled.”

“You mean that he...”

“I’m not making any accusations just yet. If we’re going to clear Junior, we must find out exactly what happened the night of the shooting.”

They entered Steele’s room, and Mason started a keen-eyed search.

Mrs. Gentrie said, “I thought I heard him come in about half-past two or three o’clock this afternoon. He seemed to be in very much of a hurry, rushing around. I’m quite sure it must have been Mr. Steele. He didn’t say anything to us, however. Usually he looks in on us just to pass the time of day when he comes home in the afternoon that way.”

“Does he come home frequently during the middle of the afternoon?”

“Sometimes. Very seldom during the morning, but occasionally he comes in the afternoon.”

Mason opened a closet door, looked inside at the array of clothes. “Do you know how he was dressed?” he asked.

Mrs. Gentrie indicated a light gray checked suit. “Why, that’s the suit he was wearing this morning.”

“Is it indeed?”

“Yes, he must have come and changed to a heavier suit. I notice his tweed is missing.”

Mason moved over to the light checked suit and calmly started going through the pockets.

“Oh,” Mrs. Gentrie said, “I... do you think it’s all right to do that?”

Mason said, “I think we’ve got to find out everything we can about him.”

“I know, but isn’t that rather — well...”

Mason said, “I think it will be all right.” He glanced significantly at Della Street and said, “Get Mrs. Gentrie to show you where he keeps his linen, Della.”

Della, distracting Mrs. Gentrie’s attention, said, “I suppose in this drawer...” She stopped at the expression on Mason’s face as the lawyer pulled a telegram from a side pocket of the coat Steele had discarded.

“Well, well, what’s this?” Mason said.

“Really,” Mrs. Gentrie protested as Mason unfolded the yellow oblong of paper. “I’d prefer that you didn’t read that.”

Mason, however, already had the telegram opened and was reading the message. “Well,” he said, “this is something. It’s a telegram sent to Steele at the office of the architect and says, ‘Man named Carr Luceman accidentally shot self when cat knocked gun off table. Luceman’s address thirteen-o-nine Delington Avenue, San Francisco. Grab plane investigate.’ And it’s signed K. Anamata.”

Mrs. Gentrie, visibly perturbed, said, “I wish, Mr. Mason, you could handle this without prying into Mr. Steele’s business.”

Mason said, “Don’t you see, Mrs. Gentrie? Steele got this room for a purpose. He must have made a habit of opening this door at night after you folks had retired, quietly sneaking down the cellar stairs, going through the garage door, and across to the flat next door. If he didn’t go inside the flat, he at least snooped around the windows and got a line on what was going on inside the place.”

“Why... why, I can’t believe it.”

“And,” Mason went on, with a significant glance at Della Street, “he’s very apt to be over there right now.”

“But why should he want to spy on the people over there?”

Mason said, “He’s evidently in the employ of some Japanese. I understand Lieutenant Tragg thinks some of the people over in that flat could tell something about the smuggling of arms into China.”

“You mean Mr. Hocksley?”

Mason said, “There’s evidence indicating that Hocksley has been engaged in Chinese gun-running for years.”

“Well, good heavens!”

“And Steele evidently secured this room because it gave him such an excellent opportunity to keep an eye on what was going on next door.”

“Well, I’ll declare! Why, then he must have been — he must — why, Mr. Mason, that would make him...”

“Exactly,” Mason said.

“Then don’t you think we’d better communicate with the police, Mr. Mason?”

“Not yet,” Mason said. “Just keep quiet so we don’t disturb anyone. We’ll do a little investigating on our own.”

Mason led the way to the cellar door, opened it silently, tiptoed down the cellar stairs. Mrs. Gentrie clicked a light switch which flooded the cellar with brilliance.

Mason inched his way over toward the shelf where the preserves were kept, keeping his eyes, however, on the garage door. “Now, as I understand it, this is the door which was painted. Your husband painted it the evening of the murder... Where is he, by the way?”

She said, “I made him go to bed. He couldn’t have done any good by sitting up, and he’s going to have a hard time at the store waiting on all of the customers without Junior to help him. That’s one thing about my husband. No matter what happens, he can sleep like a log. I don’t think he ever actually worries about anything. I don’t mean by that he isn’t concerned over the situation. He simply doesn’t worry about it. If he knew he was going to be executed tomorrow, I don’t think he’d lose a minute’s sleep. He’d simply say, ‘Well, if it’s going to be that way and there’s nothing I can do about it, there’s no reason for losing any sleep over it.’ ”

Mason turned then, casually, so he could look at the shelf on which he had placed the can. Apparently, the can had not been disturbed. He noticed that Della Street was also looking at it. She turned, caught his eye, then looked hastily away.

Mason said, “Now, is there any chance that your son could have got his fingers in that paint in some other way than off the garage door? Your husband must have brought this paint home when he came from the hardware store.”

“That’s right, but he didn’t mix it until after Junior had gone out.”

“Now, this door, I take it,” Mason said, “is not kept locked.”

“No. It isn’t. But the outer door to the garage is. There’s a spring lock on that, and Mr. Hocksley has the keys to it. I believe he has three or four duplicate keys.”

Mason said, “Let’s take a look in his garage.” He opened the door and stepped inside. “Is there a light in here?”

“Yes. There’s a drop light somewhere, and a string that turns it on. Here it is.”

She pulled the string and clicked a light on.

“There’s no automobile here in the garage,” Mason said.

“No. The police took the one that was here. There were bloodstains on the cushions, and they wanted to take fingerprints and things like that. They’ve never brought the car back.”

“I see. Now this door on the side opens into the yard which communicates with the flat.”

“That’s right. But you’ve been over this before, Mr. Mason.”

“I know,” Mason said, “but I want to be sure I’ve got the thing correctly fixed in my mind. There’s a spring lock on this door. It can be opened from the inside without a key. And by pressing that catch, the latch can be held back so the door isn’t locked. Just as it is now.”

Mrs. Gentrie looked at it and said, “Why, land sakes! That door is unlocked! We always keep that locked. I remember looking at it just this morning, and it was locked then. The latch was in position.”

“Then,” Mason said, “quite obviously, the lock must have been changed, either by someone who had a key, unlocked it from the outside and threw the catch into position, or by someone who entered the garage through the cellar of your home, Mrs. Gentrie. Now, of the people who live in the other house, Mr. Hocksley has either been killed, or has disappeared. His housekeeper has been murdered. Opal Sunley, who acted as stenographer, is the only one who remains. Was she there today, do you know?”

Mrs. Gentrie said, “I saw her going to the flat this morning — and I don’t know why, for the life of me. There certainly couldn’t have been any work for her to do.”

“Well, of the people in your house, who could have been down here? Mr. Steele?”

“Well, he might have been. He does have the run of the house like a member of the family. When Mr. Gentrie is down here, Steele will come down to talk with him for a While; but it’s in the same way he helps Rebecca with her crossword puzzles, just something to furnish an excuse for a visit.”

“The children were here after school?”

“Yes, the younger children.”

“Junior didn’t get home until quite late, as you’ve mentioned?”

“Yes.”

“Rebecca was here?”

Mrs. Gentrie shook her head. “No. Rebecca had that crossword-club meeting this afternoon, and then went to the opera from there.”

“What time did she get in?”

“Around midnight. She was full of talk about the opera, and a lot of gossip that didn’t interest me in the least.”

“Now, she went upstairs to bed without coming down to the cellar?”

“Yes. She was all dressed up in her best bib and tucker. You couldn’t have got her near the cellar.”

“Who else was down here? Your husband?”

“Yes, Arthur was down here. He spends a good deal of time here in the evenings. But I’m quite sure Arthur would never have left that door unlocked. He’s very methodical about those things.”

Mason thought that over for several seconds. Abruptly, he turned away from the door. “I guess on second thought,” he said, “there’s no use making any further investigation at this end. Better lock that door now, hadn’t you?”

Mrs. Gentrie snapped the catch on the door. “Yes, we’ll leave it locked. I don’t like the idea of having that door left unlocked. Anyone could come into the house without our knowing it — just walk right in.”

Mason said, “That’s right. Why don’t you put a lock on that door that leads to the cellar? There’s no necessity for anyone who uses the garage to use the cellar, is there?”

“No. There really isn’t. I was telling Arthur sometime ago we should have a lock put on there, but after we’d rented it to Mr. Hocksley, it looked a little as though we might have been suspicious of him. Arthur said we should either have put it on at the time we first rented the garage to him, or else wait until after he’d moved out and we had another tenant.”

“Yes, that sounds logical,” Mason said, and yawned. “Well, it’s time for me to turn in.”

Della Street was watching him closely, her forehead puckered into a curious frown.

Mrs. Gentrie made no attempt to conceal her concern. She asked, “What am I going to do about Junior? I’ve got to do something for him. That’s what I wanted to see you about. Isn’t there something we can do? And what about Steele?”

“Let it go until noon,” Mason said. “By that time, I’ll have found out just what Tragg’s planning to do. In all probability, he just wanted to make the boy talk and used that method to do it.”

“Well, he won’t talk, not as far as that woman is concerned.”

Mason started for the cellar stairs. “Well, there’s nothing more we can do tonight.”

“You’ll find out about Junior in the morning?”

Mason nodded. “First thing,” he promised.

“Please be quiet going out,” she requested. “I don’t want anyone to know I was down in the cellar at this hour, or that I’ve been up so late.”

At the front door, Mason whispered, “Try and get some sleep if you can. There’s nothing you can do. I’ll get busy just as soon as things open up. Good night.”

He opened the car door for Della Street. She jumped in with a quick, lithe motion, then switched on the dome light and looked over behind the rear seat.

Mason laughed. “Why the precautions?”

She said, “I haven’t felt easy in my mind since you set that trap and used yourself as bait.”

“You noticed the can was still on the shelf?” Mason said.

“Uh huh. That must mean that it was Steele who was getting the messages.”

Mason started the car. “There are one or two other possibilities.”

“Such as what?”

“Tragg nabbed Junior before he had a chance to go down in the basement.”

She thought that over, said, “That’s right,” then remained silent. Just before Mason turned into her street, she said, “I guess I haven’t what you call a logical mind. The more I think of it, the dizzier I get.”

Mason said, “Go to sleep and forget it.”

She showed him that she was worried. “Look here, are you holding out on me?”

“What makes you think that?”

“Because when the police find Steele’s body, we’ve got our necks in a noose, yet all of a sudden you’re acting as though there was no particular hurry.”

“There isn’t,” he said.

“Sometimes I could slap you!”

“Here’s my cheek,” he said. Then, after a moment, “If that’s a slap, I’ll turn the other cheek.”

Della laughed lightly as she jumped from the car. “Don’t forget to wipe off that lipstick. ’Night!”

“ ’Night,” Mason said, and stood watching her as she ran swiftly up the steps of her apartment house.