Members of a loving family -- George and Ann Farber, their son Georgie, and their dog -- arrive at their lake house. Their next-door neighbor, Fred, is seen with two young men, Peter and Paul, who seem to be friends or relatives. The young men come over to borrow eggs. Ann is in the kitchen cooking while George and Georgie are outside by the lake, tending to their boat. They seem friendly, and they admire a golf club belonging to George.
After leaving, Peter and Paul return with the eggs broken. They request more eggs, which also end up broken, Ann becomes frustrated, but when George tries to force the men to leave, Peter breaks George's leg with the golf club. The family is taken hostage.
The family is forced to participate in a number of sadistic games in order to stay alive. Paul asks if George or Ann wants to bet that they will be alive by 9:00 in the morning, doubting that they will be. Between playing their games, the two men keep up a constant patter. Paul frequently ridicules Peter's weight and lack of intelligence. He describes a number of contradicting stories of Peter's past, though no definitive explanation is ever presented as to the men's origins or motives.
Georgie tries to escape. He attempts to climb a locked gate but changes his mind and goes to the neighbors' empty house. Georgie attempts to shoot Paul with a shotgun, but the gun fails to go off. Paul returns him to the living room, along with the shotgun.
The men play a new game, saying whoever gets counted out will be shot. Georgie panics and makes a run for his life, which results in Peter shooting and killing him. Paul is a little annoyed that Peter didn't follow the rules of their game to the letter.