He touched his head and saw Mandrake. “What are you doing with that thing in your hand?” he demanded. “Do not point at me. It is a firearm. What has happened?” Mandrake fidgeted uneasily with the automatic and curled the toes of his right foot in an attempt to avoid that pestilent shoe-nail. Hart rubbed the back of his hand across his mouth and shook his head vigorously.

Jonathan said: “We are armed because we have come to speak with a murderer.”

Hart uttered a sound of exasperation. “Mr. Royal,” he said, “how often am I to explain that I know nothing about it? Am I to be awakened at intervals during the night to tell you that I was in my bath?”

“What, again!” Mandrake ejaculated.

“Again? Again!” shouted Hart. “I do not know what you mean by again. I was in my bath at the time it was done. I know nothing. I did not sleep all last night. For weeks I have been suffering from insomnia, and tonight I have taken a soporific. If I do not sleep I shall go mad. Leave me alone.”

“There is the body of a murdered man downstairs, Dr. Hart,” said Mandrake. “I think you must stay awake a little longer to answer for it.”

Hart sat up in bed. His pyjama jacket was unbuttoned and the smooth whiteness of his torso made a singularly disagreeable impression on Mandrake. Hart was fully awake, now; on his guard, and sharply attentive.

“Murdered?” he repeated, and to Mandrake’s astonishment he smiled. “I see. So he has done it after all. I did not think he would go so far.”

“What the devil are you talking about?” Jonathan demanded.

“He is killed, you say? Then I am speaking of his brother. I guessed that the brother set that trap. A booby-trap you call it, do you not? He betrayed himself when he reminded them of the tricks they played in their childhood. It was obvious the lady still loved her first choice. He was attractive to women.” He paused and rubbed his lips again. Jonathan and Mandrake found nothing to say. “How was it done?” asked Hart.

Jonathan suddenly began to stutter. Mandrake saw that he was beside himself with rage. He cut in loudly before Jonathan had uttered a coherent phrase —

“Wait a moment, Jonathan.” Mandrake limped nearer to the bed. “He was killed,” he said, “by a blow on the head from a stone club that hung with other weapons on the wall of the smoking-room. He was bending over the wireless. His murderer must have crept up behind him. No, Jonathan, wait a minute, please. A short while before he was killed, Dr. Hart, we were all in the library, and we heard him turn on the radio. You will remember that the smoking-room is between the library and the green sitting-room, called ‘boudoir’—the room that you were in, alone. You will remember that it communicates with both these rooms and with the hall. With the exception of Mr. Royal, who did not enter either of the other two rooms, none of us left the library after we heard the wireless until Lady Hersey went in and found him there— murdered.”

The uneven patches of red in Hart’s cheeks were blotted out by a uniform and extreme pallor.

“This is infamous,” he whispered. “You. suggest that I–I killed him.” With a movement of his hand, Mandrake checked a further outburst from Jonathan.

“I could not,” said Hart. “The door was locked.”

“How do you know?”

“After you had gone, I tried it. He had turned that intolerable thing on again. I could not endure it. I admit — I admit I tried it. When I found it locked I–I controlled myself. I decided to leave that room of torture. I came up here and to bed. The door was locked, I tell you.”

“The door from the hall into the smoking-room was not locked.”

“I did not do it. There must be some proof. It is the brother. The brother hated him as much as I. It is a pathological case. I am a medical man. I have seen it. He had stolen the mother’s love and the girl still adored him.”

“Dr. Hart,” said Mandrake, “it is not Nicholas Compline who is dead. It is his brother, William.”

In the silence that followed Mandrake heard a door, some distance down the passage, open and close. He heard voices, a footfall, somebody coughing.

“William,” repeated Hart, and his hands moved across his chest, fumbling with his pyjama coat. “William Compline? It cannot be William. It cannot.”

They did not have a great deal of trouble with Dr. Hart after that. He seemed at first to be completely bewildered and (the word leapt unbidden into Mandrake’s thoughts) disgusted. Mandrake found himself quite unable to make up his mind whether Hart was bluffing, whether his air of confusion, his refusal to take alarm, and his obstinate denials were false or genuine. He seemed at once to be less panic-stricken and more helpless than he was when he believed, or feigned to believe, that the victim was Nicholas. He also seemed to be profoundly astonished. After a few minutes, however, he roused himself and appeared to consider his own position. He gave them quite a clear account of his own movements, from the time Mandrake left him alone in the green boudoir, until he fell asleep. He said that he had taken some minutes to recover from his breakdown in Mandrake’s presence. He was fully roused by tentative noises from the wireless, not loud but furtive. He found these sounds as intolerable to his raw nerves as the defiant blasts that preceded them. They must have affected Hart, Mandrake thought, in much the same way as he himself was affected by stealthy groping in chocolate boxes at a play. The intermittent noises continued, snatches of German and French, scraps of music, muffled bursts of static. Hart imagined Nicholas Compline turning the dial control and grinning to himself. At last the maddened doctor had rushed to the communicating door and found it locked. He had not, he seemed to suggest, meant to do more than expostulate with Nicholas, turn off the wireless at the wall switch and leave the room. However, the locked door checked him. He merely shouted a final curse at Nicholas and decided to fly from torment. He switched off the lights in the “boudoir,” and went upstairs. As he crossed the hall to the foot of the stairs, he passed the new footman with his tray of glasses. He said the man saw him come out of the “boudoir” and that Hart was about half-way up the first flight when the man returned from the smoking-room and moved about the hall. He was still in the hall, locking up, when Hart reached the half-way landing and turned off to the left-hand flight. “He will tell you,” said Hart, “that I did not enter the smoking-room.”

“You could very easily have finished your work in the smoking-room before the man came,” Jonathan said, icily. “You could have returned to the ‘boudoir’ and come out when you heard the man crossing the hall.”

Mandrake, by a really supreme effort of self-control, held his tongue. He wanted with all his soul to cry out: “No! Don’t you see, don’t you see…” He knew Jonathan was wrong, off the track altogether. He was amazed at Jonathan’s blindness. Yet, because he felt certain that somewhere, beyond his own reach, lay the answer to Hart’s statement, he said nothing. Better, he thought, to wait until he had that answer.

“His skull is fractured, you say.” Hart’s voice, more composed than it had been since their last inverview, roused Mandrake to listen. “Very well, then. You must lock up the room. The weapon must not be touched. It may have the assassin’s finger-prints. The door into the hall must be examined by the police. A medical practitioner must be found. Naturally I cannot act in the matter. My own position…”

“You!” Jonathan ejaculated. “Great merciful Heavens, sir—”

Again Mandrake interrupted. “Dr. Hart,” he asked, “suppose the rest of the party agreed, would you be prepared, in the presence of witnesses, to look at the body of William Compline?”

“Certainly,” said Hart promptly. “If you wish, I will do so, though it can serve no purpose. In view of your preposterous accusations, I will not prejudice myself by making an examination, but I am perfectly ready to look. But I repeat you must immediately procure a medical man and communicate with the police.”