Police officer Nick Spitz and his wife Audrey take a trip to Italy for their 15th wedding anniversary. During their flight, they meet Charles Cavendish, who invites them to spend a weekend in Monaco on his family yacht. The guests on board the yacht include Tobey, Suzi Nakamara, Grace Ballard, Colonel Ulenga, Sergei Radjenko, Maharajah Vikram, and Juan Carlos Rivera. Charles’ uncle is a billionaire by the name of Malcolm Quince, who recently wed Charles’ ex-fiance Suzi. Suzi is a young and exotic beauty. Grace Ballard is a well-known actress, with unknown relation to the family. Tobey is the son of Malcolm set to inherit the 70 billion dollar fortune. Colonel Ulenga is the best friend of Malcolm and Sergei Radjenko is the bodyguard of the Colonel. Maharajah Vikram Shivan Govindan is from Mumbai, his relation to the family is also unknown. Juan Carlos Rivera is the non-english speaking godson of Malcolm and a Grand Prix race car driver.
During dinner, Malcolm discusses his will declaring all his invited guests as leeches that will not be included in it. In his new will he is leaving his entire fortune to his betrothed in case of his demise and Grace exited during the scene. As Malcolm began to sign his new will the lights went out, a struggle occured, and a single gunshot was heard. When the lights came back on Malcolm was found stabbed with a family heirloom, Colonel Ulenga is seen holding a gun, and Grace re-entered the room. Tobey was eliminated as a suspect after being found dead with a suicide note confessing to his father’s murder.
Upon arrival in France Inspector Laurent Delacroix investigated the murder; as the only uninvited guests officer spitz and his wife were his prime suspects. Officer Spitz and his wife investigated the other guests and any motives they had for committing the murders. Juan Carlos’ father was also a race car driver for Malcolm Quince; he became an amputee after some safety measures were ignored at the behest of Mr. Quince. Many years ago Ulenga was in a coma after saving Malcolm from an explosion, during this time Malcolm married Ulengas fiance Madeleine. Madeleine died during childbirth and it is beleived their child was also deceased due to complications. During the murder investigation, Sergei was killed in his hotel room, Suzi was killed by a poison dart in broad daylight, and Cavendish was poisoned at his Villa. At this point Grace, Juan, Ulenga, and Vikram remain alive as suspects.
French inheritance laws dictate that regardless of a will, the children of the deceased inherit their parents fortunes. Grace was revealed as the daughter of Malcolm and Madeleine, and the heir to the Quince fortune. Due to their private investigation the Spitz couple became targets, on the day Suzi was killed the Spitzes were present and they were the real targets. Nick recalled that Grace was experienced in poison and blowing darts and she was implicated in Suzis death. Cavendish loved Suzi dearly and was killed to prevent retaliation. Grace was responsible for killing both Suzi and Cavendish. This theory was presented as speculation and Inspector Delacroix asked for proof. Audrey recalled that her husband hit someone with a plate during the struggle on the yacht and Grace had a visible scar on her forhead placing her at the scene of the original crime. Grace convinced Tobey to kill Malcolm and assisted him by turning off the lights. She originally proposed splitting the inheritance but then killed Tobey so that she could keep the entire thing to herself.
Sergeis murder was left unexplained and Juan Carlos accidently broke his cover and responded to a remark. On the night of Sergeis death all the other guests had an alibi; Vikram and Grace were on a date and Ulenga was seen in his room. It is revealed that Grace and Juan Carlos were accomplices and Sergei was killed in an attempt to silence the Spitzes investigation. Juan Carlos admitted to working with Grace to get revenge against Malcolm. Juan Carlos approached Grace with his plans, and Grace convinced Tobey to kill Malcolm. Upon first thought Sergei’s death made sense because he was one of the few people that knew Malcolm had another potential heir besides Tobey. Sergei’s death is clarified as an accident, with the Spitzes as the original target.