This occurs in 1976.
Travis Grady, a trucker who suffers from visions that are somehow familiar to him, is running late for a delivery one night, he decides to make up for lost time by taking a detour through Silent Hill on his way to Brahms. On the outskirts of Silent Hill, a cloaked figure darts into the road in front of him; Travis slams on the brakes and exits his truck to check on the condition of the person. Outside his truck, Travis sees a brown-haired girl in a blue uniform. Chasing after her, Travis stumbles upon a house caught in a raging fire. He sees a woman outside of the house, but before he can talk to her, Travis hears a girl's scream from inside and enters the house to find her. After making his way through the burning house, Travis discovers a severely burned young girl lying on top of an apparent sacrificial marking, and carries her outside with the safety of a seal. Upon exiting the house, he hears sirens in the distance and loses consciousness.
The next day Travis wakes up on a bench in Central Silent Hill. After recalling the events of the previous night, he travels to Alchemilla General Memorial Hospital in hopes of finding the girl's condition. At the hospital, Travis briefly meets Dr. Michael Kaufmann, but is unable to find out any information, as Kaufmann claims that the hospital has received no new patients. On the second floor of the hospital, Travis is attacked by a faceless nurse. After battling with the nurse and continuing his search in the hospital, Travis is confronted by a large mirror with an unusual reflection. On the other side of the mirror (which reveals the Otherworld), the brown-haired girl appears and Travis is transported to the hospital's Otherworld. Later on, Travis encounters a convulsing Straightjacket and, after its defeat, finds a strange triangular piece belonging to an object known as the Flauros. The brown-haired girl appears, and Travis again loses consciousness to the siren.
Back in the Fog World, Travis wakes up in the hospital lobby and meets Lisa Garland, a nurse who informs him about the sanitarium. Making his way through Silent Hill, Travis passes through the town's butcher shop (The Family Butcher), where he witnesses the murder and mutilation of a nurse by a large monster called the Butcher.
Once Travis arrives at Cedar Grove Sanitarium, he runs into Dahlia Gillespie, the woman he spotted at the fire. He questions her, and she gives convoluted and confusing answers, revealing that her daughter is Alessa Gillespie, the girl burned in the fire. During the exploration of the sanitarium, it is revealed that Travis's mother, Helen Grady, attempted to kill him when he was a child, and that she was held in the female isolation ward. Voice recordings in the sanitarium tell of how Helen claimed she was "all better now" and wanted to see her son. Travis reaches his mother's cell and finds her otherworld counterpart (Momma) trapped in a large gibbet cage. After defeating her, he finds another triangular piece and Alessa appears as Travis passes out again.
Upon waking, Travis finds a theater ticket and insinuates that he should check out Artaud Theater. In the theater's main auditorium, he finds Lisa, who describes her dream of being an actress and teases Travis, displaying her "acting skills," before leaving. Searching the theater, Travis encounters new monsters and learns that Alessa used to visit the theater when the actors were rehearsing their rendition of Shakespeare's The Tempest. The character costume of Caliban frightened Alessa, and she quietly retaliated by psychokinetically giving the actor a headache and nosebleed. Travis discovers that he can change the theater stage's props and scenery to create different Otherworlds. The final scene change reveals the dark and dreary home of the Caliban. Defeating the creature, Travis picks up another Flauros piece. By now, Travis has caught on to Alessa's patterns, but he still has a great many unanswered questions. Alessa calls the siren and Travis once again falls unconscious.
Travis wakes up in the Fog World theater and discovers the mutilated body of an Ariel. The corpse contains a key to the motel where Travis and his father Richard Grady stayed while visiting his mother. Travis makes his final trek through the streets of Silent Hill, passing through Andy's Books and a general store, and arrives at the Riverside Motel.
Travis struggles through a long and dangerous stay at the Riverside Motel, involving many monsters previously unseen in Silent Hill, numerous transitions between the Fog World and the Otherworld, and various puzzles and searches. Travis eventually battles the Butcher, slaying it and using its blade to impale its corpse. Travis continues to seek answers regarding his family, and finds Dr. Kaufmann and Lisa Garland in a room with drugs and sexual tension between them; Lisa angrily storms out of the room, and Dr. Kaufmann follows her after threatening Travis and locking the exit. Travis escapes using a mirror in the bathroom and finally finds the key to the room in which he and Richard stayed many years ago. After opening the door to Room 500 and walking down a long diagonal shaft to another doorway, a flashback reveals that his father hanged himself from a noose here. Richard's reanimated corpse tells Travis it's time he "faced up to what happened," and morphs into a screaming, tubular monster (Sad Daddy) trapped in a box hanging from the ceiling. Travis painfully defeats the memory of his father and receives yet another piece of the Flauros. This time, Travis is visibly shaken and turns on Alessa when she inevitably appears. Once again sirens ring out and Travis collapses.
Having fulfilled his purpose in the motel, Travis awakens in the basement of the hospital. Inside, he finds the center piece of the Flauros, and reconstructs the mystical item. Exiting the hospital, Travis is accosted by Dahlia, who accuses him of freeing Alessa. Turning back, Travis sees Alessa has regained her powers as she distorts the town into a burning, nightmarish state. He escapes into the streets of Otherworld Silent Hill, otherwise referred to as "Nowhere". Using a child's scribbled map, Travis escapes an overwhelming number of monsters and makes his way to the Green Lion Antiques shop, labeled on the map as "Go Here." At the shop, Travis finds members of the Order performing another ritual on the burned Alessa. Travis is sedated with sleeping gas and drawn into a strange, nightmarish reality in which he faces the entity within the Flauros. Travis defeats the demon, and back in the antiques shop, a light shoots out of the Flauros and hits Alessa, creating a glowing, infant-like form on top of her body.
Travis has successfully moved on from his past and finds himself back in the real world. While walking down the highway out of town, Travis sees his truck; he gets in, and sees Alessa holding a baby) in his rear-view mirror. Travis smiles, taps his speedometer to reset it and show a fresh start, and drives away.