Written by the late, great Jimmy Sangster (The Revenge of Frankenstein, Taste of Fear), this supernatural riff on Agatha Christie's And Then There Were None is a gruesome, hugely entertaining chiller. Two American architects (real-life couple Katharine Ross and Sam Elliott, who met on the set of this film) are holidaying in England and find themselves trapped at a country mansion where the various guests become victims in a series of unexplained and increasingly violent deaths. Director Richard Marquand (Return of the Jedi, Jagged Edge), making his feature-film directing debut, deftly balances horror and grisly black humour. The film also boasts sumptuous photography by the great Dick Bush and Alan Hume, a wonderfully eccentric score by Michael J Lewis and a superb supporting cast which includes Charles Gray, Margaret Tyzack, Ian Hogg, John Standing and The Who's Roger Daltrey.