我最好的朋友哈利

麦可与克莱儿这对不稳定的夫妻，带著女儿去渡假。该死的热天气，搞得塞在车里的全家人都处于精神崩溃、歇斯底里的边缘，然而奇迹出现了，那是哈利！与麦可在加油站意外重逢的高中同学，一路随他们下乡渡假。喔！哈利，完美的哈利，他热情、大方、有钱、风趣。他的哲学是，当车子在路途中故障了，就换一辆车！当有人阻碍你的幸福快乐时，就干掉他。于是惊人的事情即将爆发！Michel, his wife Claire and their three little daughters Jeanne, Sarah and Iris are traveling to their cottage in Switzerland to spend summer vacation. When they stop the car, Michel goes to the toilet and a man stares at him. Soon the man introduces himself as Harold "Harry" Balestoro, who studied with Michel in high school and knows him very well. When Michel and his family go to their car, Harry parks his Mercedes Benz and introduces his fiancée Plum to the couple and invites themselves to travel to Michel's house for a drink. Later her recalls by heart a poem written by Michel and shows that he was obsessed for Michel. Harry is surprised that Michel does not write anymore and tells that he is wealthy since he has inherited his father's investments. Michel and Claire are middle-class and are still repairing their cottage by themselves. Harry and Plum stay for the night in the guest room and in the morning, Harry gives a 4x4 V6 Pajero to his new friends. They do not accept but Michel needs to bring his parents to see their granddaughters and drives the truck. He brings his mother and his father that immediately recognizes Harry. He feels tension between Michel and Claire and his parents and Harry and Plum move to a nearby hotel. During the night, Harry decides to help his friend, showing that he is a psychopath that turns Michel's life upside down.