"I know," said Alleyn, "I've been through the same process myself. Now look here, Fox. It seems to me there are one or two key pieces in this puzzle. One is the, to me, inexplicable fact that Surbonadier kept that sheet of paper with the experimental signatures: Edward Wakeford, Edward Wakeford, Edward Wakeford. I say inexplicable, in the light of any theory that has been advanced. Another is the evidence of the prints on the typewriter. A third is the behavior of Stephanie Vaughan last night in Surbonadier's flat. Why did she pretend one of her letters was missing and get me hunting for it? I may tell you I left a folded piece of plain paper in the iron-bound box. While I was out of the room she took that paper. Why? Because she thought it was the document she was after."

"The Mortlake letter or the signatures?"

"Not the Mortlake letter. Why should she risk all that to save Saint?"

"The signatures then?"

"I think so. Now put that together with the fragment of conversation Mr. Bathgate overheard this morning, and what do you get?"

"The fragment of conversation," said Fox slowly.

"Exactly."

"I believe you're right, sir. But have you got enough to put before a jury?"

"I've got a man down at Cambridge now, ferreting about in past history. If he fails I'm still going for it. The reconstruction to-morrow morning will help."

"But he won't be there—Saint, I mean."

"You are going to climb Jacob's ladder for me tomorrow, my Fox kin."

The telephone rang. Alleyn answered it.

"Hullo. Yes. Where? But what about our men at the doors? Simon's Alley. I see. Well, get back to it and if he comes out detain him. I'll be there. No, don't go in alone. How long have you left the place? I see. Get back there quickly."

Alleyn clapped the receiver down.

"Fox," he said, "we're going to the Unicorn."

"Now?"

"Yes, and damn' quick. I'll tell you on the way."

CHAPTER TWENTY

Exit Props