"I know, I know; but this ain't a threat. It's only a reconstruction of what happened. Look here: you worked up a disguise-and-cut-and-run scheme as fancy as any in a thriller. If you'd scooped a sackful of real money, it would 'a' been high crime; as it stands it's only comic. But that's not all. You broke down when a bogus copper only touched you on the shoulder, and in the first couple of hours of your criminal career you got shut up in a lavatory while an inspector walked off with your bag and your shirt. In short, you let yourself be bamboozled even out of counterfeit money. Your inspirin' personality may smooth things over and let people pardon you for thieving. But there's one thing that'll stay with you. I don't mind crooks, myself. I got several in my employ as it is. I don't care whether they're good Christians. But I do care whether they're good crooks."
Serpos made an assenting gesture.
"In order," he suggested, "to spare you the necessity of being a good detective? I quite see the point, of course. And I could also ask-having learned most of the story of what has happened tonight — whether, in the matter of foolish behaviour, there is much to choose between you and me?" He smiled, with ineffable calm. "Oh, no, my friend. Your attitude is very ingenious and amusing, but you must see that I am not taken in by it. Not for a minute."
Again Serpos considered.
"It's to be admitted that I made a mistake. I am not bound to explain anything to you: but I submit here that it was a reasonable mistake."
"I dunno," growled H.M., inspecting his fingers. He was very gentle. "That's the one part that'll be so hard for everyone to swallow — why you thought that slush was real money. Grantin' that you were away at the time Willoughby was nabbed, still you must have heard something about the case. You were right here. You surely didn't think that all that money belonged to Charters, and that he just brought it home casually and shoved it into his safe? Didn't you ask any questions at all? Any copper on point-duty from here to Bristol could 'a' told you what it was. Well, then? Why did it have to be you that made the bloomer?"
Serpos appeared to consider this from every angle, like a cat putting out its paw to touch something on the floor.
"Yes, I must tell you that," he said. "It is not that I knew too little about the case. The mistake was made because I knew, or thought I knew, too much about it. Perhaps you will allow me to ask Sergeant Davis a few questions?"
"Yes. Sure. Go ahead."
Davis glowered. down on Serpos, but he stood at attention again.