A young women jumps from a window and runs through town and country to escape some men who are pursuing her. As the story unfolds, it emerges that she is Marianne, a nightclub dancer, who is on the run from her father, a disbarred corrupt judge who lives in a villa in Portugal with Marianne's half-sister Hildegarde. On her 21st birthday, Marianne is due to receive a large inheritance from Ruth, her mother and a former lover of the judge. The money is in a
Swiss bank account along with a safebox containing legal papers incriminating her father. He and Hildegarde want the account number from Marianne so that they can access the money, which Ruth stole from the judge, and dispose of the evidence. While evading her father's henchmen, Marianne encounters Sebastian, and after they strike up a relationship, they arrive in London where she reluctantly agrees to marry him. During the ceremony, Marianne suddenly suspects Sebastian's motives and tricks the registry clerk into believing that she is really marrying Eli Frome, Sebastian's
best man, whose name he puts on the marriage certificate instead of Sebastian's. Marianne then breaks up from Sebastian, and she and Eli become romantically involved. Sebastian, who is also Hildegarde's lover, travels to Portugal and informs the judge of Marianne's marriage to Eli. The judge promises Sebastian a large amount of money if he can bring Marianne to Portugal. Eli is abducted and threatened by two men, but gets away after stabbing one of them. Sebastian returns to London, and Marianne, wanting to make peace with her father, willingly flies to Portugal with Sebastian and Eli. At the villa, a deadly game of cat-and-mouse ensues as Sebastian and Hildegarde attempt to obtain the account number out of Marianne by locking her in an overheated sauna. Discovering that they intend to harm Marianne, the judge drives away to get help, but he uses Sebastian's car on which Sebastian had sabotaged the brakes before offering it to Eli; the car plunges off a cliff, killing him. Marianne breaks out of the sauna and runs away to evade Sebastian and Hildegarde. Outside the house, she comes across a policeman and asks for his help, and he takes her to the police station where she is asked to identify a body, and she is shocked to see it is Eli, who has been murdered by Sebastian. Then, Sebastian and Hildegarde lure Marianne to an old abandoned building, where they attack and torture her for the account number. Marianne fights them off and runs, and Sebastian, giving chase, is seriously injured when he falls through a weakened floor into a cellar. Abandoning Sebastian to die, Hildegarde returns to the villa, but when she tries to seduce Rodriguez to enlist his help against Marianne, the judge's loyal manservant strangles her. Next morning, Rodriguez serves drinks and a birthday card from Eli to a grieving Marianne as they wait for the police to arrive. ==Cast==