THE MYSTERIOUS AFFAIR AT STYLES
was John, the whole thing was explained quite naturally."
"So," I cried, a light breaking in upon me, "it was John who quarrelled with his mother that afternoon?"
"Exactly."
"And you have known this all along?"
"Certainly. Mrs. Cavendish's behaviour could only be explained that way."
"And yet you say he may be acquitted?"
Poirot shrugged his shoulders.
"Certainly I do. At the police court proceedings, we shall hear the case for the prosecution, but in all probability his solicitors will advise him to reserve his defence. That will be sprung upon us at the trial. And—ah, by the way, I have a word of caution to give you, my friend. I must not appear in the case."
"What?"
"No. Officially, I have nothing to do with it. Until I have found that last link in my chain, I must remain behind the scenes. Mrs. Cavendish must think I am working for her husband, not against him."
"I say, that's playing it a bit low down," I protested.
"Not at all. We have to deal with a most clever and unscrupulous man, and we must use any means in our power—otherwise he will slip
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