Terror by Night is a 1946 Sherlock Holmes crime drama directed by Roy William Neill and starring Basil Rathbone and Nigel Bruce.

[2] In London, Vivian Vedder verifies that a carpenter has completed a coffin for her recently deceased mother's body, which she is transporting to Scotland by train.

The train makes an unexpected stop to pick up several Scottish policemen, led allegedly by Inspector McDonald.

When the lights are turned on again, the officers leave the train with Lestrade, his coat covering his face, believing he is Moran.

As the train departs, Lestrade captures the thieves in the railway station, and Holmes reveals to Watson and Moran that he recognized McDonald as an impostor and recovered the diamond from him during the fight.