O nascimento de Poirot

Who could I have as a detective? I reviewed such detectives as I had met and admired in books. There was Sherlock Holmes, the one and only - I should never be able to emulate him. (…) I settled on a Belgian detective. I allowed him slowly to grow into his part. He should have been an inspector, so that he would have a certain knowledge of crime. He would be meticulous, very tidy (…). And he should be very brainy – he should have little grey cells of the mind – that was a good phrase: I must remember that – yes, he would have little grey cells.

Agatha Christie em An Autobiography