1933. Hercule Poirot, older and greyer, receives letters threatening murder. The sender signs themselves only as โA.B.C.โ When he takes the letters to the police looking for help, Hercule finds all his old friends have moved on. But soon there is a murder and the once-great detective must take matters into his own hands.
John Malkovich is Poirot in tense new Agatha Christie adaptation