Police psychologists review recordings of a man (Robert De Niro), who states his name as Detective David Fisk, the "Poetry Boy" killer. The Poetry Boy earned the moniker for his modus operandi of murdering criminals and leaving short poems with their bodies. Fisk reveals that he looks up to his partner of almost 30 years, Tom Cowan (who the audience is led to believe is the character portrayed by Al Pacino), and considers him to be his role model of how a cop should be. Pacino's character is known by the nickname "Rooster" and De Niro's by "Turk," and they are referred as such outside of the recordings.
Charlie Sheen and Lindsay Lohan get together to make a sex tape with over 20 cameras beside Sheen's bed. The time-lapsed tape fast forwards through the two doing all sorts of bedroom antics, including gymnastics, riding a horse, and having clowns jump in under the sheets. Sheen is pulled into the air by a paranormal force and thrown against walls, shelves, and doors until he lands on the bed again. Lohan is frightened so she decides to go home when she flies into the air as well; she becomes possessed and throws him into the camera and kills him. The text explains that Sheen's body was found that day but he didn't stop partying until days later, and that his three kids were found missing, Lohan was arrested, again, and a reward was put out for the missing children.
Kate and John Coleman (Vera Farmiga and Peter Sarsgaard) are experiencing strains in their marriage after their third child was stillborn. The loss is particularly hard on Kate, who is also recovering from alcoholism. The couple decides to adopt a 9-year-old Russian girl, Esther (Isabelle Fuhrman) from a local orphanage. While Kate's and John's deaf daughter Max (Aryana Engineer) embraces Esther immediately, their son Daniel (Jimmy Bennett) is less welcoming. Kate suspects that there might be problems in Esther's background when Esther's knowledge of sex extends beyond her age. Her suspicions deepen when Esther seriously injures another girl who had bullied her.
As an old man nearing the end of his life, Adso, youngest son of the Baron of Melk recounts how, as a young novice in 1327, he accompanied his mentor, the Franciscan friar William of Baskerville to a Benedictine abbey in Northern Italy. The abbey had been chosen as the site for a theological debate between the Franciscan order and the Pope on the poverty of Christ. The abbey is already home to a famed scriptorium where scribes copy, translate or illuminate books. The mysterious recent death of the monk Adelmo of Otranto - a young but famous illuminator - has stirred fears among the abbey's devout inhabitants. The Abbot seeks help from William, known for his deductive powers. The illuminator's death cannot be dismissed as a suicide because the body was found at the foot of a tower having only a window which cannot be opened. William is reluctant to involve himself, though he is persuaded not only because of the intellectual challenge, but also because of his desire to disprove fears of a demonic culprit in Adelmo's death. William is also motivated to act by his fears that the Abbot will summon officials of the inquisition if the mystery remains unsolved.
Twenty years after the events of Halloween and Halloween II, on October 29, 1998, Marion Chambers (Nancy Stephens), Dr. Sam Loomis' former colleague, returns to her house in Langdon, Illinois, to find it has been burglarized. Her teenage neighbor Jimmy (Joseph Gordon-Levitt) searches the house and finds nothing. While waiting for the police in her house, Marion discovers a file is missing, the one on Laurie Strode (Jamie Lee Curtis), Michael Myers' sister who escaped the attacks two decades earlier. She also realizes that someone has been in her house and immediately rushes back over to Jimmy's house, where she finds him and his friend dead. Michael Myers (Chris Durand) appears, and attacks Marion before slitting her throat, killing her. The police arrive as Michael leaves the house with Laurie's file.
In 1888, Mary Kelly (Heather Graham) and her small group of London prostitutes trudge through unrelenting daily misery. When their friend Ann Crook (Joanna Page) is kidnapped, they are drawn into a conspiracy with links higher up than they could possibly imagine. The kidnapping is soon followed by the gruesome murder of another woman, Martha Tabram (Samantha Spiro); and it becomes apparent that they are being hunted down, one by one as various prostitutes are murdered and mutilated post-mortem.
A young American woman, Greta, takes a job as a nanny in a remote English village. When she arrives, she discovers that the 8-year-old boy she was hired to care for is actually a life-size porcelain doll that the parents treat like a real boy, as a way to cope with the death of their son. After violating a list of strict rules, disturbing events lead Greta to become increasingly convinced that the doll might actually be alive.
At a gas station, Michelle Mancini (Natasha Gregson Wagner) fights off an apparent attack by a stuttering attendant (Brad Dourif). However, he was actually trying to warn her of an attacker in the back seat, and as Michelle drives off, the attacker in the back seat decapitates her with an axe. On a college campus, student Parker Riley (Michael Rosenbaum) relates how one of the campus halls, Stanley Hall, had been the site of a massacre in 1973. The story is discredited by school journalist Paul Gardner (Jared Leto).
On the night of October 31, 1963, in Haddonfield, Illinois, 6-year-old Michael Myers (Will Sandin) murders his older sister Judith (Sandy Johnson) by stabbing her with a kitchen knife. Fifteen years later, on October 30, 1978, Michael escapes Warren County Smith's Grove Sanitarium, where he had been committed since the murder. He steals the car that was to take him to a court hearing, the intention of which was for him to never be released.
A group of scientists are killed by a mutant named Pluto (Michael Bailey Smith). Later, Bob Carter (Ted Levine) and his wife, Ethel Carter (Kathleen Quinlan) are traveling from Cleveland, Ohio to San Diego, California for their silver anniversary. With them are their teenage children Bobby (Dan Byrd), and Brenda (Emilie de Ravin), eldest daughter Lynn (Vinessa Shaw), Lynn's husband Doug Bukowski (Aaron Stanford), their baby daughter Catherine (Maisie Camilleri Preziosi), and their German Shepherds, Beauty and Beast.
In 1974, a woman makes a wax sculpture as one of her sons eats breakfast. Her husband enters with another son. After being strapped and taped into his chair, he scratches his mother's hand. Then she slaps the child across the face.
A Los Angeles Police Department veteran 9-1-1 operator, Jordan Turner (Berry), receives a call one night from a teenage girl, Leah Templeton (Evie Thompson), fearing for her life as a man breaks into her home. Jordan calmly advises her to conceal herself upstairs, but when the call is disconnected, Jordan calls Leah back, a decision that later costs Leah her life, as the ringing phone gives her location away to the intruder. Jordan attempts to dissuade him from going further over the phone. He responds "It's already done" and hangs up, leaving her distraught. The next day, Jordan sees a television report confirming that Leah has been murdered. Emotionally affected by the incident, Jordan tells her boyfriend, Officer Paul Phillips (Morris Chestnut), that she can no longer handle field calls.
Predatory lenders Simone and Eddie awaken on either side of a room split by a cage containing a scale, wearing head harnesses with screws poised to pierce their temples. They learn via videotape that the one who sets more flesh weight on their tray will survive. Eddie cuts fat from his torso, but Simone chops off her arm, which tilts the scale in her favor; the timer expires, and Eddie is killed by the screws. While he reviews the game's footage, Detective Lt. Mark Hoffman is called to the scene by FBI Agent Dan Erickson, who found Agent Peter Strahm's fingerprints around the room. Also present is Agent Lindsey Perez, whose survival was covered up by Erickson for her protection. They learn from Dr. Adam Heffner, who performed all of the autopsies for the Jigsaw case, that the knife used to cut the jigsaw piece from Eddie's flesh was only used on Seth Baxter before then. The agents intend to find the Baxter videotape to prove Strahm's involvement.
In Queens, New York during October 1999, John Sullivan (Caviezel), a 36-year-old homicide detective, breaks up with his girlfriend Samantha (Melissa Errico) with the reason partially attributed to the trauma caused by the death of his fireman father Frank (Quaid). Still living in the same house where he grew up, he discovers his father's Heathkit single-sideband ham radio and begins transmitting radio signals. Because of highly localized electro-temporal spatial effects caused by unusual aurora borealis activity, John somehow makes contact with his father exactly 30 years in the past on the day before Frank's death in a warehouse fire. The ensuing conversation results in Frank thinking John is a stalker. Before the connection cuts out, John is able to shout out the circumstances that led to Frank's death. The next day as little things brought up in their conversation prove true, Frank believes and heeds John's words, escaping the fire to safety. The father and son reconnect on the HAM radio set later that evening, with Frank sharing his dreams and his hopes for his son, and John recounting the details of the Mets-Orioles World Series, which is just beginning in Frank's timeline in 1969. John also reveals to Frank that he now dies of lung cancer in 1989 due to his smoking habit.
On one side of town, a babysitter and the kids she is babysitting are brutally murdered. The police find that the murderer used his bare hands to tear them to shreds. The shot then changes to teenager Jill Johnson (Camilla Belle) who is going through a teenage crisis, having her boyfriend, Bobby (Brian Geraghty), cheat on her with her best friend Tiffany (Katie Cassidy), and going over 800 minutes on her cell phone, for which her dad, Ben (Clark Gregg), has her babysit for a wealthy family to pay the debt. The unfortunate timing causes Jill to miss out on a school bonfire which her other best friend, Scarlett (Tessa Thompson), is attending. Jill arrives at the elaborate Mandrakis House, which has a greenhouse built in the center. The parents (Derek de Lint and Kate Jennings Grant) show her around and tell her about their live in housemaid Rosa (Rosine Ace Hatem). Mrs Mandrakis then gives Jill their numbers, stating that they won't be back until midnight. As the kids (Arthur Young and Madeline Carroll) are seen to be upstairs asleep, Jill soon begins to receive anonymous phone calls.