Two best friends, Steven Craven and Nico Bradley, travel to Mexico to have some fun. They meet a vagrant in a bar that gives a puzzle box to Nico. When he opens the device, he finds that it is a key to hell. Nico brings Pinhead that inflicts pain to him and Steven and the youngsters vanish.
Later, in Los Angeles, Dr. Ross Craven, his wife Sarah and their daughter Emma receive Peter and Kate Bradley to have dinner. Both families miss Steven and Nico and they hired a private detective to seek them out, but he only finds Nico's backpack.
When Emma snoops around the backpack, she finds the puzzle box and out of the blue, Steven returns covered of blood. But soon they discover that it is not Steven's soul that is inside his body.