Archie was not a man who readily allowed himself to become worried, especially about people who were not in his own immediate circle of friends, but in the course of the next week he was bound to admit that he was not altogether easy in his mind about his father-in-law's mental condition. He had read all sorts of things in the Sunday papers and elsewhere about the constant strain to which captains of industry are subjected, a strain which sooner or later is only too apt to make the victim go all blooey, and it seemed to him that Mr. Brewster was beginning to find the going a trifle too tough for his stamina. Undeniably he was behaving in an odd manner, and Archie, though no physician, was aware that, when the American business-man, that restless, ever-active human machine, starts behaving in an odd manner, the next thing you know is that two strong men, one attached to each arm, are hurrying him into the cab bound for Bloomingdale.

He did not confide his misgivings to Lucille, not wishing to cause her anxiety. He hunted up Reggie van Tuyl at the club, and sought advice from him.

"I say, Reggie, old thing--present company excepted--have there been any loonies in your family?"

Reggie stirred in the slumber which always gripped him in the early afternoon.

"Loonies?" he mumbled, sleepily. "Rather! My uncle Edgar thought he was twins."

"Twins, eh?"

"Yes. Silly idea! I mean, you'd have thought one of my uncle Edgar would have been enough for any man."

"How did the thing start?" asked Archie.

"Start? Well, the first thing we noticed was when he began wanting two of everything. Had to set two places for him at dinner and so on. Always wanted two seats at the theatre. Ran into money, I can tell you."

"He didn't behave rummily up till then? I mean to say, wasn't sort of jumpy and all that?"

"Not that I remember. Why?"

Archie's tone became grave.

"Well, I'll tell you, old man, though I don't want it to go any farther, that I'm a bit worried about my jolly old father-in-law. I believe he's about to go in off the deep-end. I think he's cracking under the strain. Dashed weird his behaviour has been the last few days."

"Such as?" murmured Mr. van Tuyl.

"Well, the other morning I happened to be in his suite--incidentally he wouldn't go above ten dollars, and I wanted twenty-five-and he suddenly picked up a whacking big paper-weight and bunged it for all he was worth."

"At you?"

"Not at me. That was the rummy part of it. At a mosquito on the wall, he said. Well, I mean to say, do chappies bung paper-weights at mosquitoes? I mean, is it done?"

"Smash anything?"

"Curiously enough, no. But he only just missed a rather decent picture which Lucille had given him for his birthday. Another foot to the left and it would have been a goner."

"Sounds queer."

"And, talking of that picture, I looked in on him about a couple of afternoons later, and he'd taken it down from the wall and laid it on the floor and was staring at it in a dashed marked sort of manner. That was peculiar, what?"

"On the floor?"

"On the jolly old carpet. When I came in, he was goggling at it in a sort of glassy way. Absolutely rapt, don't you know. My coming in gave him a start--seemed to rouse him from a kind of trance, you know--and he jumped like an antelope; and, if I hadn't happened to grab him, he would have trampled bang on the thing. It was deuced unpleasant, you know. His manner was rummy. He seemed to be brooding on something. What ought I to do about it, do you think? It's not my affair, of course, but it seams to me that, if he goes on like this, one of these days he'll be stabbing, someone with a pickle-fork."

To Archie's relief, his father-in-law's symptoms showed no signs of development. In fact, his manner reverted to the normal once more, and a few days later, meeting Archie in the lobby of the hotel, he seemed quite cheerful. It was not often that he wasted his time talking to his son-in-law, but on this occasion he chatted with him for several minutes about the big picture-robbery which had formed the chief item of news on the front pages of the morning papers that day. It was Mr. Brewster's opinion that the outrage had been the work of a gang and that nobody was safe.

Daniel Brewster had spoken of this matter with strange earnestness, but his words had slipped from Archie's mind when he made his way that night to his father-in-law's suite. Archie was in an exalted mood. In the course of dinner he had had a bit of good news which was occupying his thoughts to the exclusion of all other matters. It had left him in a comfortable, if rather dizzy, condition of benevolence to all created things. He had smiled at the room-clerk as he crossed the lobby, and if he had had a dollar, he would have given it to the boy who took him up in the elevator.

He found the door of the Brewster suite unlocked which at any other time would have struck him as unusual; but to-night he was in no frame of mind to notice these trivialities. He went in, and, finding the room dark and no one at home, sat down, too absorbed in his thoughts to switch on the lights, and gave himself up to dreamy meditation.

There are certain moods in which one loses count of time, and Archie could not have said how long he had been sitting in the deep arm-chair near the window when he first became aware that he was not alone in the room. He had closed his eyes, the better to meditate, so had not seen anyone enter. Nor had he heard the door open. The first intimation he had that somebody had come in was when some hard substance knocked against some other hard object, producing a sharp sound which brought him back to earth with a jerk.

He sat up silently. The fact that the room was still in darkness made it obvious that something nefarious was afoot. Plainly there was dirty work in preparation at the cross-roads. He stared into the blackness, and, as his eyes grew accustomed to it, was presently able to see an indistinct form bending over something on the floor. The sound of rather stertorous breathing came to him.

Archie had many defects which prevented him being the perfect man, but lack of courage was not one of them. His somewhat rudimentary intelligence had occasionally led his superior officers during the war to thank God that Great Britain had a Navy, but even these stern critics had found nothing to complain of in the manner in which he bounded over the top. Some of us are thinkers, others men of action. Archie was a man of action, and he was out of his chair and sailing in the direction of the back of the intruder's neck before a wiser man would have completed his plan of campaign. The miscreant collapsed under him with a squashy sound, like the wind going out of a pair of bellows, and Archie, taking a firm seat on his spine, rubbed the other's face in the carpet and awaited the progress of events.

At the end of half a minute it became apparent that there was going to be no counter-attack. The dashing swiftness of the assault had apparently had the effect of depriving the marauder of his entire stock of breath. He was gurgling to himself in a pained sort of way and making no effort to rise. Archie, feeling that it would be safe to get up and switch on the light, did so, and, turning after completing this manoeuvre, was greeted by the spectacle of his father-in-law, seated on the floor in a breathless and dishevelled condition, blinking at the sudden illumination. On the carpet beside Mr. Brewster lay a long knife, and beside the knife lay the handsomely framed masterpiece of J. B. Wheeler's fiancee, Miss Alice Wigmore. Archie stared at this collection dumbly.

"Oh, what-ho!" he observed at length, feebly.

A distinct chill manifested itself in the region of Archie's spine. This could mean only one thing. His fears had been real............