The Sergeant weighed this suggestion on its merits. "Three of them said that it was."
"Four, counting Miss Herriard," agreed Hemingway.
"Four's too many to be in a conspiracy," said the Sergeant positively.
"The valet said that he couldn't get any answer to his knock. I don't recall that he said he had tried the door."
"You mean," said the Sergeant slowly, "that you think maybe he only knocked, and when Stephen Herriard came up it was he who forced the latch, and turned the key quickly afterwards, when no one was looking?"
"I don't think anything of the kind," said Hemingway. "I have got an open mind."
"What did you make of the cigarette-case, sir?"
"It doesn't look too good for Master Stephen, on the face of it."
"No; but that's complicated too, isn't it, sir? I mean, there seems to be plenty of evidence to show that the last person known to be in possession of the case was Miss Dean."
"Look here!" said Hemingway. "I can accept the theory that Stephen walked in here to have a quiet chat with his uncle over a cigarette (though, mark you, on the evidence it doesn't seem likely), but what I can't swallow is the suggestion that Miss Dean did. Get hold of the valet for me, will you?"