1hr 56mins
Dir: Billy Wilder
Starring: Charles Laughton and Marlene Dietrich

A veteran British barrister nearing retirment must defend his client in a murder trial

This hugely enjoyable and critically acclaimed courtroom drama is based on the 1953 Agatha Christie stage play of the same name and was nominated for six academy awards. It features a scene in the buffet at Euston station, which appears to be a set with a combination of back-projection and matted backdrops being used.

This is the station scene in the film. That does appear to be Euston station through the open door so my guess is that this is a set with some back-projection.
However, in this later shot the ‘departure board’ visible through the right hand window has gone, suggesting further that this is a set. As well as back-projection, some matted backdrops are likely to have been used.