The Timeless Allure of Hercule Poirot

Between 1920 and 1975, Agatha Christie wrote 33 books starring Hercule Poirot, a mustachioed detective who uses the “little grey cells” in his brain to solve the most perplexing murders.

Each of the books has been adapted at least once into a TV series or film. Murder on the Orient Express has been adapted the most — five times, including a new release starring Kenneth Branagh.

The chart below shows how many times each of the books was adapted, and when.