her ribs. She retrieves the key from a beaker of acid as instructed, but the lock does not open and the trap inevitably kills her. Dr. Lynn Denlon is abducted from the hospital she works at and brought to the now bedridden John Kramer. His apprentice, Amanda, locks a collar armed with five shotgun shells around Lynn's neck that is connected to John's heart rate monitor and will detonate if she moves out of range or John dies. Lynn is instructed by Amanda to keep him alive until another test subject has completed his game; the victim, Jeff, a grief-stricken father who was consumed with vengeance after the death of his son Dylan in a drunk driving accident, must undergo a series of tests at an abandoned meatpacking plant to confront those involved in the case. Jeff's first test leads him into a meat freezer where he finds Danica, the only witness to the accident (who refused to testify in court) naked and chained to a metal frame inside the plant's freezer, with nozzles inside the frame spraying her with water to quicken her hypothermia. Jeff retrieves the key after Danica persuades him to help her, but she freezes to death before he can do so. In his next test, Judge Halden, who passed a lenient sentence on the driver who caused Dylan's death, is chained at the neck to the bottom of a vat. Rotting pig carcasses are dropped into a grinder that slowly fill the vat until Jeff saves him by burning Dylan's belongings in an incinerator to retrieve a key. His third test involves Timothy, the driver who killed Dylan, who is strapped to a machine that will slowly twist his limbs and then his head. The key is tied to the trigger of an enclosed shotgun that goes off after Jeff retrieves it, killing Halden. Jeff fails to save Timothy in time; the machine breaks his neck. Lynn is forced to perform an improvised surgery to relieve pressure on John's brain. The surgery is successful, and Lynn convinces John to order Amanda to remove the collar. However, Amanda refuses and threatens Lynn's life, having become jealous of her interactions with John. John pleads with Amanda, who admits that she no longer believes in his philosophy and had rigged Troy and Kerry's traps. Refusing to listen to John's warnings, Amanda shoots Lynn just as Jeff arrives. Jeff,