"A very nice little haul," said Inspector Marriott with approval, as he snapped on the last pair of handcuffs. "And we'll have more as time goes on, I hope."

White with rage, Dymchurch glared at Tuppence.

"You little devil," he snarled, "It was you put them on to us."

"It wasn't all my doing. I ought to have guessed, I admit, when you brought in the number sixteen this afternoon. But it was Tommy's note clinched matters. I rang up Inspector Marriot, got Albert to meet him with the duplicate key of the office, and came along myself with the empty blue envelope in my bag. The letter I forwarded according to my instructions as soon as I had parted from you two this afternoon."

But one word had caught the other's attention.

"Tommy?" he queried.

Tommy who had just been released from his bonds came towards them.

"Well done, brother Francis," he said to Tuppence, taking both her hands in his. And to Dymchurch: "As I told you, my dear fellow, you really ought to read the Classics."