"Well, Mr Hart," said my friend, after he had had a quick but thorough glance round the room. "Do you mind if I ask you a few questions?"

"Of course not."

"We both of us heard what happened from our end of the wireless. I suppose that was Tremayne"s voice all right?"

"Yes."

"Did you see him come in?"

"Yes. He came in about ten minutes before he started doing the local announcements. My office is just outside, you know. He came in to say good evening, and left his hat and coat there as he usually does. They"re still there."

"And then he went into the studio?"

"Yes. We chatted for a few minutes. I gave him the announcements that were to be read and then he came in here."

"The lights were on?"

"Yes. I came in with him. The place was just the same as it always is."

"I see. And then you left him here alone?"

"Yes. With the average performer we have someone in that box through his performance. Either I or poor Tremayne used to do that, to keep a check on the performance, but, of course, we"ve never done it with our own announcers. We always a.s.sume that they"ll be all right."

"Does Tremayne do all the announcing?"

"He used to do most of it. In fact, he did it all, unless he were away on holiday. It"s not a big staff here. It"s mainly a relay station, you see."

"I see. And so you left him in here alone?"

"Yes. When I went out, he was sitting at the microphone. I left him there and shut the door behind me. Then I went to my office to do a bit more work. It"s the end of the month and I was in rather a rush. I had been in my office most of the day."

"And what happened then?"

"Well, I had the loud speaker in my office turned on, as usual. It provides another check on the performance. I get so used to it, too, that I scarcely pay any attention to it. At least, until today."

Here he was obviously overcome by emotion.

"After a few minutes," he went on at last, "I heard exactly what you and everyone else heard."

"I see. You heard Tremayne call out that the lights had gone out and that he was being strangled?"

"That"s it."

"You couldn"t hear it directly, of course?" went on the detective.

"No. The studio"s absolutely sound-proof. I dashed to the door at once. It was still locked. My own door was open, and I can swear that no one had opened the studio door, come out, and closed it behind them. I"m sure it would have been quite impossible. Then I found that in my excitement I had left the key of the studio door on my table in the office. I dashed back and got it, opened the door and found the place in darkness."

"That"s curious," commented Garland.

"It was," said Hart. "There wasn"t the slightest sound. I groped for the switch at the door. It had been turned off. I switched on the lights and they came on all right. I thought at first that they might have fused and that Tremayne had had a kind of fit. But even that wouldn"t have explained his - Oh well! And that"s all I know. The room was just as you see it now. Absolutely empty."

"Extraordinary!"

"It is. I do hope you can do something. I"m terribly worried."

Here he broke down altogether.

"Cheer up," said Garland. "There must be some explanation. I"ll just have a bit of a look round. I wonder if you would mind getting his hat and coat from your office. I"d like to have a look at them. By the way, was there anyone else who would have seen him coming to work tonight?"

"Yes. Sergeant Jones, the commissionaire at the front door."

"Oh, yes. Would you mind sending him up? I"ll see the rest of the staff later. How many are there?"

"About a dozen."

And with that he went out, looking thoroughly miserable.

When he had gone we both had a thorough search of the room. We found absolutely nothing. The walls were solid everywhere. The only opening was the door. The floor under the carpet we soon found to be made of solid concrete. Any entrance or escape through the ceiling was out of the question. Even if there had been a trap (which there wasn"t) no one could have dropped through, strangled Tremayne, and got back again (even if he had had a ladder) in the time between the crime and the entrance of Hart.

"Very baffling," said William, with a queer smile.

"Very," I agreed.

The commissionaire at the front door came in at that moment. A typical army man was Sergeant Jones.

Yes. He had seen Tremayne come in earlier in the evening. He arrived at his usual time. He would know him out of a thousand. Very peculiar walk he had. Coat collar turned up as usual. Gla.s.ses? Yes, everything quite ordinary and as usual.

He was dismissed with a benediction.

A clerk was then produced who had pa.s.sed him coming up the stairs. He, too, was dismissed with thanks.

Sergeant Jones, recalled, said that, even supposing a body had been carried past Mr Hart"s office without being noticed, it would not go into the street without him, Sergeant Jones, seeing it. Most indignant he was about this. Of course, the thing was impossible. He was there to watch people coming in and going out, and, if he didn"t notice a body going out, he wasn"t worth his money.

"Why," he went on, "I could tell you every movement of every member of the staff today."

And he went on to enumerate a long list, finishing with Tremayne, who had come in at 5.30, and Mr Hart, who had come in at noon, and not left the office since.

Garland scratched his head thoughtfully at this information, and decided that he had learnt enough here.

"I"m going round to see Mrs Tremayne," he said to me. "And I"m sure that one"s enough for an interview with an hysterical woman who"s probably a widow. You run back to your office. I"ll give you a ring if anything else happens tonight."

With that he left me, and I walked thoughtfully back to my office.

He didn"t ring me up that night, and when I went to bed I was still as puzzled as ever by the mystery. My two reporters, good boys both, had done their best, and produced some very readable stuff, but they had not been allowed much scope by the local police, who knew their job much too well. All the newspapers could get was a very little fact and a great amount of conjecture.

And it was not an easy case to conjecture about. I, for one, was hopelessly baffled. The wife of the vanished announcer had been interviewed by my reporter as well as by the detective, and she swore that it was her husband"s voice she had heard from the loud speaker. And there was no doubt that she ought to know.

It was really most amazing. Tremayne had been attacked in an empty and unapproachable room, and then had been spirited away all in a s.p.a.ce of less than two minutes.

No wonder that next day all the newspapers were full of it. One after another they gave the case flaring headlines. Some went so far as roundly to declare that the whole thing was due to magic.

The thing was so surprising that it might have been considerably more than a seven days" wonder; but the newspapers this time were not to have a long drawn out mystery, for by the following evening Garland had drawn the net tight and all was over, bar the shouting and the scaffold. It made the story even more surprising but, as a journalist myself, I could not help thinking regretfully of the cleverness of this relative of mine, which had so soon ended the newspaper sensation of years.

I was down at the office that afternoon when the telephone bell rang. It was Garland. He wanted to see me, and I told him to come along. In a very few minutes he was shown in. He looked tired and, to my trained eye, immoderately triumphant.

"Well?" I asked.

"Very," he answered. "I want to relieve my brain, so I"ll talk to you for a few minutes. You will admit, won"t you, that it"s impossible for a man to be strangled in an empty sealed room, and also impossible for him, when he"s been strangled, to vanish from that room?"

"Yes. But was the studio sealed?"

"We examined it ourselves. The police have been over it again today. A fly couldn"t have walked out of it without being noticed. The walls are solid, the ceiling is solid, the floor is concrete. How on earth was the victim removed?"

"The only way was through the door."

"That certainly seems the only way, but you must remember this Hart was in his office all the time with his door open. He was bound to hear and see anything being taken past his door. And, even supposing that he hadn"t noticed anything, there was the commissionaire downstairs."

"He may have been bribed."

"Possible, but not very probable. Besides, there wasn"t time for anything to be carried away between the strangling and the opening of the door. Hart was in the room, he says, almost as soon as the deed was done. There"s proof, too, because you could hear someone coming into the room over the wireless."

"Did his wife tell you anything?"

"Nothing directly. She"s very attractive. No children and no sign of trouble. Husband happy at the studio. On good terms with his boss. Hart, she confided, had even condescended to come to tea once. A tremendous honour, I gathered. She"s very distraught, of course, but convinced that her husband"s alive and kicking somewhere."

"But the thing"s impossible," I cried. "The thing"s positively eerie. He"s simply vanished into thin air."

"That"s certainly what it seems like, but things you see, as Gilbert once observed, are not always what they seem."

He yawned, and then went on: "Would you like to be in at the death?"

I started.

"Of course. Is it a matter of death, do you think?"

"I don"t think. I"m sure. There"s been a particularly heartless murder; but murder will always out. It"s a thing that given a little intelligence on the other side is bound to be discovered. Take this case. There aren"t any clues. What then? Why, the very lack of them is significant. That was what got me started on the right track. Lack of clues plus logic plus (possibly) a little luck. That was the formula. And in an hour the whole mystery will be exploded. It seems rather a shame, because it was all very clever and artistic."

"It baffled me anyhow," I said.

"It baffled me for nearly twelve hours. I got quite puzzled, until I began to think of human nature. Then everything was moderately simple."

With that he looked at his watch.

"Well," he said, "if you want to be in at the death, follow me, O fourth-cousin-twice-removed."

And he led the way to a waiting police car.

He was very quiet during the journey, and my feeble attempts to make conversation soon fizzled out. Luckily, it was not a long ride. We soon stopped at a large detached house on the outskirts of the city. On the pavement were a couple of constables. After a whispered consultation, they took up their positions just inside the gate.

"Do you know who lives here?" said Garland.

"No."

"The widow of the murdered man."

Our ring was answered by a trim maid.

"Tell your mistress," he said, "that the detective"s back again and wants to see her."

The maid returned in a second and we were ushered into a sitting-room. In a corner was seated an attractive woman of about thirty. She was very pale, and obviously stricken with grief, and, when she saw us, she seemed involuntarily to shrink back from us. I could sympathise with her, and I was about to murmur my condolences when my companion spoke.

I had never heard him use such a tone before, and I was not surprised that he was the terror of criminals.

"Excuse the intrusion," he rapped out. "But I wanted to talk to Mr Hart in your presence. I asked him to come here at seven. It"s just that now."

At these words she turned so pale that I thought she was going to faint. She did not say a word, but motioned to us to sit down, and at that moment Hart came in. The maid did not announce him. At any other time I should have been surprised, but now there were too many other matters of surprise for me to think of that little detail.

He smiled at the pale woman in front of him, went over to her, and stood by her side.

"Well?" he asked.

"Sorry to worry you like this," said Garland; "but there are one or two questions I want answered, and I thought that I"d better ask them here. I like doing things on the spot."

At this the man went as pale as the woman.

"Well?"

"I wish it were," answered the other gravely. "Now, don"t let"s beat about the bush. I"m not a fool. Why did you do it?"

"Do what?" gasped the man.

"And," went on Garland, ignoring the question, "where-?"

At this query both of them looked instinctively towards a French window leading into the garden beyond. The look was only the matter of a fraction of a second but Garland noticed it.

"Ah! I thought so," he said. "Well, is there any need to go on with this farce any longer?"

"I"m afraid I don"t understand you," said the man in a self-possessed voice.

"You"re sure?"

"Quite."

"Right," said Garland, turning to me. "Go and fetch those two policemen. There are some tools in the car. Tell them to wait for me in the garden just outside the window. Our friends here will be able to watch what they"re doing nicely."

I turned to the door, and at that moment the woman let forth a scream such as I never hope to hear again. The man held her in his arms and tried to soothe her, but it was too late and, do what he could, he could not stop her from sobbing out the whole miserable story. And what a miserable story it was!

How Garland had guessed the truth I could not imagine; but he had, and now that his theories were vindicated, he looked as miserable as the two unfortunates he had trapped.