Agatha Christie. Death comes as the end (№ 157136)

- You don't understand Renisenb. Is evil that comes into the house from the outside, it attacks the mind at all, but there is an evil which is brewing inside, and nobody noticed him. It grows slowly, day by day, until you hit all around, and then the death can not be avoided.
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But what are you talking about? What evil mean?
He looked at her and suddenly smiled.
- Never mind, Renisenb. I was talking about the diseases that affect the fruits.