Simone and Eddie awaken in a room with a caged-in scale in the center, wearing head harnesses. The overweight Eddie cuts fat from his body, but Simone chops her left arm off and tips the scale in her favor, saving herself. Lieutenant Mark Hoffman is called to the scene by Dan Erickson , who found Peter Strahm's fingerprints around the room. Erickson also shows that Lindsey Perez is alive; while explaining that he protected Perez after her incident in Saw IV due to her being a target of an unknown accomplice, now believed to be Strahm. Jill Tuck meets with Hoffman at her clinic; he informs her that he is taking control of the games, and Jill hands him only five envelopes received in the box from John's will.
William Easton , executive of Umbrella Health, talks with his company's attorney about Harold Abbott , whose insurance policy was revoked after a discrepancy was found on his application and who later died from his illness. In his office, William is kidnapped and placed in a trap, with a large vise enclosing his torso, and a breathing mask covering his face. Hank , his janitor and a smoker, is in the same situation across from him. Hank is killed when he fails to hold his breath longer. In the second test,Jigsaw's puppet informs William that he must choose to save either his file clerk or secretary, named Allen and Addy respectively, and let the other die. In the end, William chooses to save Addy, and Allen is hanged by a barbed wire noose when his platform retracts. His third test takes place in a large boiler room, the company attorney, Debbie, stands at the bottom of a caged-in maze with a device on her chest set to fire a spear through her head. At the end of the maze, Debbie discovers through X-ray films that the key has been implanted in William's side, and attacks him with a circular saw, but fails to before the timer runs out and kills her. In the final test, William finds his six staff members chained to a spinning carousel with a shotgun pointed towards each person, but he can only choose to save two of the six by pushing buttons in a device that will drive spikes into his hand and divert the shotgun upward. He reluctantly chooses to save Emily and Shelby.
Meanwhile, Erickson and Perez inform Hoffman that abnormalities were found in Strahm's fingerprints, and that the scrambled voice from theSeth Baxter tape did not match Jigsaw's. They lead Hoffman to the site where the voice is being unscrambled by a technician. The moment Hoffman's voice is unscrambled from the tape, he kills all three of them and then sets bodies on fire. Tara and Brent wake up in one locked cage, while Pamela Jenkins wake up in another. The former cage contains a switch labeled "Live" and "Die". When Hoffman returns to the observation room, he finds a letter that Jill has placed on the desk, which he himself had written to Amanda and Jill enters suddenly and attacks him from behind, while William simultaneously reaches the end of his path, finding himself between the two cages. It is shown that he and Pamela are brother and sister, while Tara and Brent are the family of Harold Abbott. Now they can choose to either kill William or set him free using the marked switch next to the tank. Brent shifts the switch to "Die", and a platform of needles swings into William's back, pumping hydrofluoric acid into his body and killing him. Jill straps Hoffman to the chair and places the "Reverse Bear-Trap" on his head. She leaves Hoffman with a 45 second timer; he escapes the chair by breaking his hand and freeing himself, then jams the trap into the door's frame to stop it from fully opening, and he pulls his head free, only with his mouth partially ripped open.
