A group of passengers are heading off on a train in Paris for a trip to Rome. They are a motley collection of characters, including an adulterous couple, a film star trying to escape the limelight and a French police inspector.
Aboard is a valuable painting which is stolen, this leads to murders (though not until some way into the film). There are, of course, many suspects!
This is a fun film that takes place almost entirely on board the moving train. Neat little camera tricks and editing adds to the interest, though sometimes is a little too cute for it's own good. Conrad Veidt is excellent as the main baddie, exuding menace. Also good in the film is Gordon Harker as a very annoying man.