After midnight, a snowdrift halts the renowned Orient Express during its journey through the mountainous Balkans. The opulent train carries an unexpectedly high number of passengers for the season, yet by morning, it loses one. An American magnate is found lifeless in his compartment, stabbed numerous times, with his door secured from the inside.
Among the travelers is the well-known detective Hercule Poirot, who is on a holiday. Stranded with a potential killer among them, Poirot faces the daunting task of unveiling the murderer.