Conversations are always dangerous, if you have something to hide. - Agatha Christie

Use your eyes. Use your ears. Use your brains — -if you've got any. And, if necessary — act.

I don't think I shall ever forget my first sight of Hercule Poirot. Of course, I got used to him later on, but to begin with it was a shock, and I think everyone else must have felt the same! I don't know what I'd imagined — something like Sherlock Holmes — [...] Of course, I knew he was a foreigner, but I hadn't expected him to be quite as foreign as he was, if you know what I mean. When you saw him you just wanted to laugh! He was like something on the stage or at the pictures. [...] He looked like a hairdresser in a comic play!

To commit a successful murder must be very much like bringing off a conjuring trick.