Murder on the Orient Express
"Lie back and think – use (as I have heard you say so often) the little grey cells of the mind – and you will know!" (1.5.141)
She was not even looking at him. Her gaze went past him, out of the window to where the snow lay in heavy masses.
"You are a strong character, Mademoiselle," said Poirot gently. You are, I think, the strongest character amongst us."
"Oh, no. No, indeed. I know one far, far stronger than I am."
"And that is – ?"
She seemed to suddenly come to herself, to realize that she was talking to a stranger and a foreigner with whom, until this morning, she had only exchanged half a dozen sentences. (1.5.63-67)
"Come, my friend," said M. Bouc. "You comprehend what I am about to ask of you. I know your powers. Take command of this investigation!" (1.5.139)