The Human Centipede 2 (Full Sequence) (2011)

In the tollbooth of a parking garage in East London, Martin Lomax is watching The Human Centipede (First Sequence), a film he is obsessed with, on his laptop. Short, obese, asthmatic, and mentally challenged, Martin lives in an unkempt council flat with his emotionally abusive mother, who blames him for having his father put in prison for physically, psychologically, and sexually abusing Martin when he was a boy. Dr. Sebring, Martin's psychiatrist, touches him inappropriately, and prescribes him heavy medication.

During a home appointment with Dr. Sebring, Mrs. Lomax talks about her son's unsettling discussion of creating a twelve-person centipede. Dr. Sebring says that Martin's obsession with a twelve-person centipede, as well as Martin's pet centipede, is a "phase", relating the pain of a centipede's bite and phallic shape to the sexual abuse he endured at the hands of his father. Mrs. Lomax remains resentful and apathetic towards Martin.

Martin acquires a dingy warehouse after killing the owner and landlord, and begins abducting people to use for a twelve-person human centipede. His victims include a young couple, a man and his pregnant wife, and two drunk girls who catch Martin masturbating with sandpaper. Martin's mother finds and destroys his scrapbook in disgust after unsuccessfully attempting a murder-suicide. When Mrs. Lomax attempts to dispose of his centipede, Martin throws his centipede on her face, which bites her. After killing her by bludgeoning her head with a crowbar, Martin then lures his detested neighbour, Dick, to the scene, before shooting and kidnapping him.

Back at the tollbooth, Martin catches Dr. Sebring and a taxicab driver having sex (as well as oral sex with a prostitute) on one of the CCTV security cameras. Martin kills Sebring in a fit of rage and abducts the others. Martin's final victim is Ashlynn Yennie, the actress who played Jenny in The Human Centipede, whom Martin lures under false pretenses of being Quentin Tarantino's casting agent.

Martin assembles his "centipede". Following his notes and sketches from The Human Centipede, Martin severs the ligaments in each person's knees to prevent them from fleeing and uses a hammer to knock out their teeth. Martin initially tries to mutilate the buttocks of each victim. When he cuts into the buttocks of one victim too deeply, it causes him to bleed to death. Instead of surgical tools, Martin uses a staple gun and duct tape to attach each person's lips to the next person's buttocks. The pregnant woman, who was planned to be the front of the centipede out of sympathy for her pregnancy, is presumed dead; Martin places her in the corner. Martin's "human centipede" is ultimately ten people long with Ashlynn in front.

Martin experiments by having his centipede walk around and force-feeds Ashlynn cream-of-mushroom soup using the funnel and tube when she refuses to eat from the dog bowl. Disturbed by Ashlynn's screams, he tears her tongue out with pliers. Martin soon starts rubbing on his victims' stomachs in hopes that they defecate. When they don't, this angers Martin. He then injects each victim with a laxative, forcing them to uncontrollably and violently defecate into the mouth of the person behind them in a chain-like reaction, causing all the victims to swallow each other's excrement, much to Martin's excitement. He wraps his genitals in barbed wire and rapes the woman at the back of the centipede. The pregnant woman awakens and runs outside screaming, in labour. She leaps into a victim's car and gives birth. When Martin pursues her, she stomps on the accelerator, crushing her baby's skull in the process, and drives away.

Martin returns to the warehouse and finds that the centipede has separated into two halves after one victim was able to free his lips from another victim's buttocks. Furious that his centipede is ruined, Martin kills the victims via gunshot and stabbing with a knife. As he hesitates to kill Ashlynn, she punches him in the crotch and shoves the funnel into his rectum, before dropping his pet centipede into it. Martin fatally stabs her in the neck and staggers out in agony.