One cannot be interested in crime without being interested in psychology. It is not the mere act of killing, it is what lies behind it that appeals t… - Agatha Christie

Once I went professionally to an archaeological expedition--and I learnt something there. In the course of an excavation, when something comes up out of the ground, everything is cleared away very carefully all around it. You take away the loose earth, and you scrape here and there with a knife until finally your object is there, all alone, ready to be drawn and photographed with no extraneous matter confusing it. That is what I have been seeking to do--clear away the extraneous matter so that we can see the truth--the naked shining truth.

I'm used to that. It often seems to me that's all detective work is — wiping out your false starts and beginning again.

Murder, you see, is an amateur crime... One feels, very often, as though these nice ordinary chaps, had been overtaken, as it were, by murder, almost accidentally. They've been in a tight place, or they've wanted something very badly, money or a woman - and they've killed to get it. The brake that operates with most of us doesn't operate with them... They continue to be aware that murder is wrong, but they do not feel it. I don't think, in my experience, that any murderer has really felt remorse... Murderers are set apart, they are 'different' - murder is wrong - but not for them - for them it is necessary - the victim has 'asked for it,' it was 'the only way.