Freddy snarled: "Welcome to my nightmare" as he propelled Jason around the interior of the boiler room like he was in a pinball machine ("Tilt").Scriptwriter Sidney Howard wrote the screenplay based upon his 1934 stage adaptation of Sinclair Lewis"" 1929 novel of the same name.The three characters caught in the conflict were:Tony Wendice (Ray Milland) - a charming, sophisticated yet villainous British husband and ex-tennis professional at Wimbledon, who married for money, and was obsessively jealous about his wife""s affairMargo Wendice (Grace Kelly) - an unfaithful wealthy, and beautiful socialite wifeMark Halliday (Robert Cummings) - a handsome American crime-mystery writerMastermind Tony Wendice blackmailed (or ""influenced"") C."His wife answers an emergency phone call from foreman Earl, who asks for Roy - one of his power company""s technicians:Neary, get into your truck and report to line N in Tolono.