Being a detective is not always the nicest job, really, so it should come as no surprise that most detectives are a mite peculiar, having witnessed human nature too many times at its worst. Our favorite fictional detective, Hercule Poirot, is a strange little man. Here, perhaps, is why:
“Mon ami,” said Poirot, “I like to inquire into everything. Hercule Poirot is a good dog. The dog follows the scent, and if, regrettably, there is no scent to follow, he noses around—seeking always something that is not very nice. So also, does Hercule Poirot. And often—oh! so often—does he find it!”
from Peril at End House