In 1978 Victoria, Mark "Chopper" Read is an inmate at Pentridge Prison, and the film follows the brutal arc of his violence-fueled world inside and beyond the prison walls. Keithy George, Simon Lyndon, another inmate, points to a line in the yard and warns Mark not to cross as it marks the Painters and Dockers’ territory. The very next day, Mark crosses that line and stabs Keithy multiple times, setting off a violent chain of retaliation. A fierce contract is issued: the Painters and Dockers place a $10,000 bounty on Mark, and the violence that follows pulls in others from the fringes of Melbourne’s criminal scene.
Mark conscripts Bluey Barnes and Jimmy Loughnan to help him lead a siege against the dockers, a reckless effort born from a mix of loyalty, pride, and an appetite for control. When Jimmy tries to back out of the suicide mission, he shanks Mark, slashing his own arm to claim self-defense. Mark survives and is placed back in a separate cell from Bluey and Jimmy, but the trouble doesn’t end there. It is revealed that Mark is serving a long sentence—sixteen and a half years—for the attempted abduction of a judge, a scheme intended to free Jimmy Loughnan and reshape the men’s fates.
A confrontation with the prison board over a transfer for security purposes leads to a brutal turn: the board declines the change, and Mark has his ears cut off so he can relocate to a mental health wing to finish his sentence. The act is a stark reminder of the cost of defiance within the system, and it marks a new phase in Mark’s already violent story.
After his release from prison, Mark reconnects with his former girlfriend Tanya. At a club, a jealous rage erupts and he fires several shots with a handgun. Back at Tanya’s house, he abuses both Tanya and her mother when he discovers Tanya on the phone with Neville Bartos, a wealthy cocaine supplier who dominates Melbourne’s western suburbs. When Neville refuses to lend Mark money, Mark shoots him in the abdomen, escalating his defiance and violence.
Mark then goes to Jimmy Loughnan’s apartment, where Jimmy lives with his pregnant fiancée Mandy and their young daughter. Mark asserts that he’s working for the police and has a “green light” to shoot criminals, claiming he has already shot Neville. He tells Jimmy that he heard about the contracts meant for him and that Jimmy was supposed to carry them out, then menacingly holds a gun to Jimmy’s head. The tension finally shifts toward reconciliation of sorts as Mark apologizes and gives money to Jimmy.
In a Bojangles car park, Sammy the Turk, an affiliate, tells Mark he wants to show him something. Mark draws a sawed-off .410 shotgun and, after a brief argument, shoots him in the eye. Mandy witnesses the murder from behind a parked car and informs Jimmy, setting in motion the film’s moral reckoning.
Mandy’s testimony becomes crucial as she turns crown witness against Mark for the murder of Sammy the Turk, revealing that Sammy had lured Mark to the car park to make Jimmy cash in on the contract — but they were led to the wrong car park. Mark escapes a murder charge but is ultimately convicted of malicious wounding of Neville Bartos, and is sentenced to five years. The story closes on a note that emphasizes the consequences of Mark’s escalating violence and the expensive toll it takes on those around him.
