And thus it was that they came to me with their story. I listened to them in silence and then put a few questions.

“Had Clevedon arranged that you should be his best man?” I asked Trevor.

“Not at all,” he said, “nothing of the sort. I met him quite by accident on Midlington station, and—”

“What date was that?”

“It was February 23rd.”

“Are you sure of that?”

“Yes, it was February 23rd right enough, because that was the day I had to be in London. It had been fixed up with the lawyer chaps, Finns and Tregarty, who did all my uncle’s business. I went down from Blankester by a train that stops five minutes at Midlington—beastly hole it is, too! Looking out, I saw Billy on the platform. We were at school together, you know, and then in France—good pals. He pulled me out of a damned mess once—a good story that, which I’ll tell you some day. He’s one of the very best, is Billy. I shouted out to him, ‘Billy, Billy,’ and he came up. ‘Good egg, Jimmy,’ he said, ‘I was getting a bit fed up with my own company.’ There was a vacant corner seat, and he took it and we travelled to London together.”

“What time would that be?” I interrupted.

“Let’s see; it was the 11.23 at Midlington, and 4.7 in London. We put up at the Terminus Hotel, both of us, had dinner there, and went to see Jimson’s Joy Ride at the Lyric. Then we trotted round to one or two places we know of and got back to the Terminus at 1 a.m., and so to bed, as What’s-his-name would say.”

“If we could make absolutely sure of the date—” I began.