“They tried to be too clever---and that was their undoing.”

“Real evidence is usually vague and unsatisfactory. It has to be examined---sifted. But here the whole thing is cut and dried. No, my friend, this evidence has been very cleverly manufactured---so cleverly that it has defeated its own ends.”

“Is she a very clever little actress, acting a part? Or is she a genuine semi-moronic suicidal victim?”

“You might start a new religion yourself, with the creed: 'There is no one so clever as Hercule Poirot, Amen, D. C. Repeat ad lib.'!”

“It will prove, I fear, too Herculean a task for us.”

“People who can be very good can be very bad too.”

“One knows so little. When one knows more it is too late.”