“Well, it was like this. We were talking about detective stories. Una—that’s her name—is just as keen about them as I am. We got talking about one in particular. It all hinges on an alibi. Then we got talking about alibis and faking them. Then I said—no, she said—now which of us was it that said it?”
“Never mind which of you it was,” said Tuppence.
“I said it would be a jolly difficult thing to do. She disagreed—said it only wanted a bit of brain work. We got all hot and excited about it and in the end she said ‘I will make you a sporting offer. What do you bet that I can produce an alibi that nobody can shake?’
“Anything you like, I said, and we settled it then and there. She was frightfully cocksure about the whole thing. ‘It’s an odds on chance for me,’ she said. ‘Don’t be so sure of that,’ I said. ‘Supposing you lose and I ask you for anything I like?’ She laughed and said she came of a gambling family and I could.”
“Well?” said Tuppence as Mr. Jones came to a pause and looked at her appealingly.
“Well, don’t you see? It is up to me. It is the only chance I have got of getting a girl like that to look at me. You have no idea how sporting she is. Last summer she was out in a boat and someone bet her she wouldn’t jump overboard and swim ashore in her clothes, and she did it.”
“It is a very curious proposition,” said Tommy. “I am not quite sure I yet understand it.”
“It is perfectly simple,” said Mr. Montgomery Jones. “You must be doing this sort of thing all the time. Investigating fake alibis and seeing where they fall down.”
“Oh—er—yes, of course,” said Tommy. “We do a lot of that sort of work.”