In this atmospheric British gothic mystery, two young teachers travel to the Yorkshire Moors in search of a missing friend, only to encounter a reclusive pianist haunted by his past in the Spanish Civil War. As storms rage and paranoia mounts, they must confront secrets, suspicion, and danger inside an isolated house.

Från IMDB:
A pair of young teachers look into the disappearance of their friend in the Yorkshire Moors. They soon run across the man they suspect is the murderer, and have to sit out a storm with him.