Is Spiral: From the Book of Saw Scary? The Verdict and the Whole Plot

The Fourth of July ends in a subway tunnel

On the Fourth of July, Detective Marv Bozwick is off duty at a parade when he chases a thief into a sewer pipe. Someone in a pig mask attacks him from behind. He wakes up with his tongue pinned in a subway tunnel where trains still run, and a recorded message gives him a choice: rip out the tongue and live, or stay put and be killed by the next train. This is the scene to brace for, and it happens at the very start of the movie. He cannot free himself before the train arrives, and he dies. The trap looks like the work of the old Jigsaw Killer, though that man is dead, so the movie has a case to solve.

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The killer works through the police department

The next morning, Captain Angie Garza gives Detective Zeke Banks a new partner, an idealistic rookie named William Schenk. They investigate Bozwick's death, and Zeke recognizes the trap as the old Jigsaw method. Soon Detective Fitch, who once ignored Zeke's call for backup and nearly got him killed, is taken and put in a trap in which a device will tear off his fingers or he will be electrocuted as a basin fills with water. He fails and dies. Some officers start to suspect Zeke, because of his history with Fitch. The station receives a box holding a pig puppet, some of Schenk's tattooed skin, and a vial that points to a butcher shop that used to be a hobby shop Zeke and his father visited. The team finds a tape recorder and a skinned corpse there, which is identified as Schenk. Zeke's father Marcus, a retired chief, goes looking for the killer himself and is taken. Garza is abducted next and locked into a trap in the cold storage room at the precinct, where she must cut her own spine on a blade to stop boiling wax from pouring onto her face. She does not manage it, and Zeke finds her body.

A bobby pin is the most useful tool in the warehouse

Zeke follows a lead, gets captured and wakes up at a warehouse with his wrist cuffed to a pipe and a hacksaw lying nearby. He thinks about sawing off his arm, then gets free with a loose bobby pin. In the next room he finds his old partner Peter Dunleavy, who went to prison after Zeke exposed a murder Dunleavy committed. Dunleavy is chained in front of a glass-crushing machine that has been rigged to throw shrapnel. A tape recorder tells Zeke he can free the man or let him die. Zeke tries to save him and cannot get the key in time. In another room he finds Schenk, who faked his own death with the skinned body of the thief he had used as bait for Bozwick, and who has been the copycat all along.

Schenk explains his grievances in a warehouse

Schenk tells Zeke that his real surname is Emmerson. His father, Charlie Emmerson, was murdered by Dunleavy after he agreed to give evidence against a corrupt cop. He also says that Zeke's father Marcus, while chief, protected corrupt officers on purpose to clean up crime faster under an arrangement called Article 8. Schenk thinks Zeke could be an ally and gives him a final test: Marcus hangs above the floor and is slowly bleeding out. Schenk calls 9-1-1 and says a shooter is chasing him, which sends a SWAT team. He gives Zeke a revolver with one bullet and a choice. Zeke can shoot a target to save Marcus and let Schenk escape, or shoot Schenk and let Marcus bleed. Zeke shoots the target, and Marcus's restraints loosen and lower him to the floor.