The player controls Torque, a man who has been sent to Abbott State Penitentiary on Carnate Island, Maryland. Torque has been convicted and sentenced to death for murdering his ex-wife and two children, although he claims to have blacked out at the time this happened and cannot remember anything. The night Torque arrives, there is a powerful earthquake, which releases an army of monsters upon the facility. Torque's cell door breaks and he is freed from captivity. Starting from his cell, Torque traverses the prison in an attempt to escape Carnate Island alive.
During the journey, Torque finds that the monsters set loose personify the many forms of execution the island has played host to. In addition, he is met by the spirits of some of Carnate's most famous residents: the deranged psychologist Dr. Killjoy, the former executioner Hermes T. Haight, and the regretful murderer Horace. With their help, Torque discovers that he can transform into a raging monster himself (other characters assert that these "transformations" are merely a sort of adrenaline-fueled madness). Killjoy is obsessed with curing Torque, though his methods are questionable, and at various points delivers vague medical advice. Horace and Hermes, on the other hand, try to sway Torque towards good or evil, respectively. Torque meets several other characters along the way, whose fate is variable. For example, he can team up with a corrections officer while traversing the island's forest.
At the climax of the game, Torque is confronted by visions of his deceased family. Depending on the player's actions, they will either forgive Torque (because it was not him who murdered them) or blame him for their troubles (because it was him, either in whole or in part). After facing his inner demon, himself, and a monster born of his hatred, Torque is found by a rescue boat, though his fate past this point is dependent on what his family thinks of him. Depending on his actions, Torque will: be rescued and get a re-trial; knock out the driver and escape; or become his inner demon, kill the driver, and run back into the island.