Excellent little mystery, sort of a precursor to The Lady Vanishes (also scripted by Launder & Gilliat). This time a body appears on a train, instead of disappearing from one, though a separated train car does serve as a trap for the protagonists in both films.

Lowe and Cummings make a fine team, and the dialogue is sharp. The plot is a bit rushed because of the short screen time, but a wonderful film nonetheless.