“Well, I don’t see what else it can be.” “But why should he want to throw it away?” “Because it has now done its work, whatever it was, and he wants to wash his hands of the passage. He’d throw the passage away if he could. I don’t think it matters much one way or another, and I don’t suppose there’s anything to find in the cupboard, but I feel that we must look.” “Do you still think Mark’s body might be there?” “No. And yet where else can it be? Unless I’m hopelessly wrong, and Cayley never killed him at all.” Bill hesitated, wondering if he dare advance his theory. “I know you’ll think me an ass—” “My dear Bill, I’m such an obvious ass myself that I should be delighted to think you are too.” “Well, then, suppose Mark did kill Robert, and Cayley helped him to escape, just as we thought at first. I know you proved afterwards that it was impossible, but suppose it happened in a way we don’t know about and for reasons we don’t know about. I mean, there are such a lot of funny things about the whole show that—well, almost anything might have happened.” “You’re quite right. Well?” “Well, then, this clothes business. Doesn’t that seem rather to bear out the escaping theory? Mark’s brown suit was known to the police. Couldn’t Cayley have brought him another one in the passage, to escape in, and then have had the brown one on his hands? And thought it safest to hide it in the pond?” “Yes,” said Anthony thoughtfully. Then: “Go on.” Bill went on eagerly: “It all seems to fit in, you know. I mean even with your first theory—that Mark killed him accidentally and then came to Cayley for help. Of course, if Cayley had played fair, he’d have told Mark that he had nothing to be afraid of. But he isn’t playing fair; he wants to get Mark out of the way because of the girl. Well, this is his chance. He makes Mark as frightened as possible, and tells him that his only hope is to run away. Well, naturally, he does all he can to get him well away, because if Mark is caught, the whole story of Cayley’s treachery comes out.” “Yes. But isn’t it overdoing it rather to make him change his underclothes and everything? It wastes a good deal of time, you know.” Bill was pulled up short, and said, “Oh!” in great disappointment. “No, it’s not as bad as that, Bill,” said Antony with a smile. “I daresay the underclothes could be explained. But here’s the difficulty. Why did Mark need to change from brown to blue, or whatever it was, when Cayley was the only person who saw him in brown?” “The police description of him says that he is in a brown suit.” “Yes, because Cayley told the police. You see, even if Mark had had lunch in his brown suit, and the servants had noticed it, Cayley could always have pretended that he had changed into blue after lunch, because only Cayley saw him afterwards. So if Cayley had told the Inspector that he was wearing blue, Mark could have escaped quite comfortably in his brown, without needing to change at all.”