On a one-week Mediterranean pleasure
cruise aboard the "Sheila," the yacht of movie producer Clinton Greene, the guests include: actress Alice Wood; her talent-manager husband Anthony Wood (nee' Blondin but he took her last name instead); talent agent Christine;
screenwriter Tom Parkman and his wife Lee; and
director Philip Dexter. All but Lee were together at Clinton's home one year before, on the night a
hit-and-run accident resulted in the death of Clinton's wife,
gossip columnist Sheila Greene. Greene, a
parlor game enthusiast, informs everyone that the week's entertainment will consist of "The Sheila Greene Memorial Gossip Game". Each guest is assigned an index card containing a secret that must be kept hidden from the others. The game's object is to discover everyone else's secret while protecting one's own. Each night, the yacht anchors at a different Mediterranean port city, where one of the six secrets is disclosed to the entire group. The guests are given a clue, then sent ashore to find the proof of who holds the card bearing that secret. The game for that night ends when the actual holder discovers the proof. Following the first day's game, suspicion begins that the "pretend" secrets are actually true. The first card says "YOU are a SHOPLIFTER" and was assigned to Philip, but it applies to Alice, who was caught shoplifting before becoming famous. On the second day, Christine almost dies when someone turns the boat's propellers on while she is swimming near them. The second secret is revealed to be "YOU are a HOMOSEXUAL". In the evening, Greene goes to the designated island and prepares for the "game" ahead of the guests. It takes place in a monastery, with all guests dressed in hooded monks' robes; in addition to the robe, Greene is dressed up as Alice, with a wig and makeup. The game does not run as smoothly as in the first night. The following day, the guests discuss the game on the yacht and notice that Greene has not returned. Returning to the monastery, they discover his corpse. Back on the yacht, Parkman suggests that Greene was murdered by one of them. He suggests that the rest should put their index cards on the table. Five cards are revealed: YOU are a SHOPLIFTER, HOMOSEXUAL, EX-CONVICT, INFORMER, and LITTLE CHILD MOLESTER. The "HOMOSEXUAL" card applies to Parkman, who had a brief encounter with Greene years before Parkman was married to Lee. Parkman reveals that he had the sixth card "YOU are a HIT-AND-RUN KILLER" and suggests that the hit-and-run killer murdered Greene to conceal their involvement in Sheila's death. Christine reveals that when she was a secretary in the film industry, during the
Second Red Scare, she informed on left-leaning actors to further her career and become a talent agent. Out of guilt, she says she now tries to help them find work. Anthony reveals that he is the "EX-CONVICT," having been jailed twice for assault, then taunts Dexter about choosing one of the two final cards. Before he does, Lee, who has been drinking, tearfully confesses to having killed Sheila while driving drunk the previous year (she was on her way to Clinton's party when she accidentally struck Sheila. Panicked, she drove back home) and to killing Clinton the previous night after he provoked her with this fact. Distraught, she locks herself in her cabin. She is later found dead, with her wrists slit, in the bathtub in Greene's cabin, and the case seems to be closed. On the final night of the cruise, the crew and most of the guests go to a party onshore, but Dexter, who brought no money, remains on the ship. Parkman sees lights on the ship blinking on and off and returns to find Dexter pondering loose ends of earlier events. Dexter suspects that Lee "killed" a dead body, and that the real murderer rearranged the scene to implicate her. Dexter points out that the six "secrets" spell out "SHEILA", except for the final letter "A", which breaks the pattern. After figuring out what the game was the first night, Parkman actually changed out his own card—"YOU are an ALCOHOLIC" (the missing A)—for a more condemning one: "YOU are a HIT-AND-RUN KILLER", knowing both secrets applied to Lee. He later arranged for Lee to see that new card, leading her to believe that the game's purpose was to expose her for her role in Sheila's death. On the second night, Parkman murdered Greene, and framed Lee for the deed. Then, he spiked her bottle of bourbon with sleeping pills, and after she drank it, carried her body into the bathtub and slit her wrists, making it seem like a suicide. Lee's estate, worth $5 million, therefore went to Parkman, making him wealthy and free of a marriage that bored him. Dexter also attempted to kill Greene with the boat's propellers to prevent his secret from coming out. Parkman tries to kill Dexter, but is stopped by Christine, who had come up to the yacht for a sexual rendezvous and has heard their entire conversation. Dexter and Christine then blackmail Parkman: In exchange for keeping the secret that he killed Greene, Parkman must finance their next film with the money from Lee's estate. ==Cast==