Murder on the Orient Express (1974) plot summary
Famed Belgian detective Hercule Poirot is travelling on the Orient Express in the winter when the train is snowed in. A man is murdered in his berth, throwing all the widely-varying passengers under suspicion. During the investigation it comes to light that the dead man was a criminal himself, responsible for the death of a little girl, and that fewer and fewer people on the train appear to be above suspicion at all.