What actually happens
Detective Matthews leaves a foot behind
After the last game, Detective Eric Matthews gets out of the bathroom he was locked in by breaking his own foot with a toilet lid. Six months later, Officer Daniel Rigg and his SWAT team find the site of another Jigsaw game. The victim, a man named Troy, tore chains out of his own body to get away from a bomb. Detective Allison Kerry notices that the room's exit was welded shut, which breaks Jigsaw's usual rule that every victim gets a chance to survive. Then Kerry is kidnapped herself and wakes up wearing a harness with hooks in her ribs. She fishes the key out of a beaker of acid, as instructed, but unlocking the harness does not stop the trap, and it kills her.
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A doctor with a collar and a timer
Dr. Lynn Denlon is taken from the hospital where she works and brought to John Kramer, who is now bedridden. His apprentice Amanda fits a collar around Lynn's neck loaded with five shotgun shells. It is connected to John's heart rate monitor, so it will go off if Lynn leaves the range or if John dies. Her job is to keep him breathing while another test subject plays out his game. That subject is Jeff, a father who has been consumed by vengeance since his son Dylan was killed years ago by a drunk driver. Jeff has to get through several tests at an abandoned meatpacking plant, and each one puts him face to face with someone connected to the case.
Jeff gets a forgiveness test with a deadline
Jeff's first test is a freezer, where Danica, the only witness to the crash, hangs naked in a metal frame while nozzles spray her with water. She refused to testify in court. Jeff gets the key after she talks him into helping, but she is dead of the cold before he gets it. Next is Judge Halden, who gave the driver a light sentence and is now chained by the neck in the bottom of a vat while rotting pig carcasses drop into a grinder above him. Jeff burns Dylan's belongings in an incinerator to get the key. The worst test comes late, with Timothy, the driver, strapped into a machine built to twist and break his arms and legs and finish with his neck. The key for it is attached to the trigger of an enclosed shotgun, and when Jeff takes the key the gun fires and kills Halden. Jeff shouts that he forgives Timothy, but the machine breaks Timothy's neck anyway.
Amanda decides to run the show
Lynn performs an improvised operation to relieve pressure on John's brain, and it works. She gets John to order Amanda to take off the collar, but Amanda refuses and threatens her, jealous of how well the two get along. John pleads with Amanda, who admits she has stopped believing what he teaches and says she rigged Troy's and Kerry's traps so they could not be beaten. Amanda ignores John's warnings and shoots Lynn just as Jeff walks in. Jeff turns out to be Lynn's husband, and he shoots Amanda with a gun John left for him. As Amanda dies, John explains that Lynn's test was really Amanda's. He knew what she was up to and would not let a murderer carry on his work.
The ending, explained
John then speaks to Jeff and offers to call an ambulance for Lynn if Jeff has learned everything from his tests. The last test is a choice between killing John and forgiving him. Jeff cuts John's throat with a power saw, which triggers Lynn's collar while the room locks itself. Before John dies, he takes out a tape recorder and tells Jeff that his daughter Corbett has also been kidnapped and that nobody else knows where she is. Amanda, Lynn, John, Kerry, Danica, Halden and Timothy are all dead by the end. Jeff is the only one who completed his game alive, and the movie stops on the news that he has another one to start.
The post-credits ruling
Nobody has confirmed either way whether Saw III has a scene after the credits.
✓ Spoiled safelyDog status: fine, no dog dies, and the pig carcasses were already dead.
Questions people ask at 1am
Is Saw III scary?
Yes, Saw III is a 7 out of 10 with medium dread and a lot of gore. Most of the fear is in the traps and how long the movie stays on them.
How does Saw III end?
Amanda shoots Lynn and Jeff shoots Amanda, then Jeff kills Jigsaw with a power saw, which sets off Lynn's collar. Jigsaw's last tape tells Jeff that his daughter Corbett has been kidnapped.
Does the dog die in Saw III?
No dog dies in Saw III. Rotting pig carcasses appear in a vat scene, but they are already dead.
Is there a post-credits scene in Saw III?
Nobody has confirmed either way whether Saw III has a scene after the credits.
Who is Amanda in Saw III?
Amanda is Jigsaw's apprentice. In Saw III she lets Lynn's collar stay on out of jealousy, and she rigged the traps Troy and Kerry were caught in so that nobody could beat them, which breaks Jigsaw's rules.
