Night of the Big Heat (1967 film)

Night of the Big Heat is a 1967 British scifi horror film released by Planet Film Productions. Based on the 1959 novel of the same name by John Lymington, the film was directed by Terence Fisher, and starred Christopher Lee, Peter Cushing, and Jane Merrow.

Jeff and Frankie Callum run the Swan, an inn and tavern on the remote Scottish island of Fara. Jeff, a novelist in his spare time, hires a secretary named Angela Roberts. Unknown to Frankie, Jeff and Angela are former lovers.The Callums moved to Fara Island so that Jeff could escape Angelas amorous advances although as far as Frankie knows, it was to escape the tedium of city life on the mainland. Angela wants to resume her fling with Jeff, despite Jeff wanting nothing to do with her. ........

Source: Wikipedia