Agatha Christie's Poirot S02 E05 The Disappearance of Mr. Davenheim

Matthew Davenheim, a rich banker, disappears on a walk from his country house to the village post office, and Inspector Japp of Scotland Yard is put onto the case. Poirot, who has developed an interest in conjuring tricks, bets Japp five pounds that he can solve the mystery without leaving his apartment.