After being on the run with her adopted father Harry Mason (Sean Bean) for nine years, 17-year-old Heather Mason (Adelaide Clemens) learns that her presumed identity is false when terrifying dreams begin to encroach upon her reality and her father disappears. With no one but new student Vincent Cooper (Kit Harington) to keep her planted in reality, Heather decides to visit the place of her nightmares, the one place her dad has warned her never to go—Silent Hill.

Silent Hill: Revelation is a sequel to Silent Hill (2006) (2006), which was based on the video game series Silent Hill by Tokyo-based Konami Corporation. The screenplay was written by Michael J. Bassett.

Heather/Sharon/Alessa locates her father tied to a statue in the Order's sanctuary under Lakeside Amusement Park. She runs to him but is stopped by Vincent's mother Claudia (Carrie-Anne Moss). Claudia welcomes Heather to Silent Hill and informs her that she will become the "incubator" for a deity worshiped by the Order, whose presence will allow them to leave Silent Hill and go into the world to cleanse it of sinners. Claudia asks for the Seal of Metatron but, when Heather gives it to here, Claudia is stripped of her facade and revealed for the monster she really is. Claudia lunges at Heather, but Pyramid Head (Roberto Campanella) steps in to protect her and ends up beheading Claudia. Meanwhile, Heather and Vincent untie Harry, and the three of them escape. Later, as they walk down the street, they notice that the ash has stopped raining down over the town. As Heather and Vincent keep walking, Harry lags behind and announces that he's going to stay in Silent Hill and look for Rose, who is still being held captive somewhere. Heather and Vincent catch a ride with a trucker who introduces himself as Travis Grady (Peter Outerbridge). Heather introduces herself as Sharon, the first time she's been able to use her real name in years. In the final scene, the truck leaves Silent Hill as a caravan of police cars and a prison bus enter it.

Michael J. Bassett didn't like the first film, so he decided to do something that he felt was truer to the game, as well as making numerous changes that fit neither the first movie nor the game series. However, doing such thing resulted in many drastic retcons. Some of the bigger changes include:

(1) In the first film, we see that it is a religious group called "the Brethren" which is an offshoot of Christianity. They burn anyone who is supposed to be a witch or go against their traditions. In the second film, the religious group is now called "the Order" from Silent Hill 3. Their belief system drastically changes to a goddess that will cleanse the world. They claim Heather is a vessel for the goddess, and that they burned Alessa knowing she would survive the fire and could be impregnated with the god. However, in the first film that was not the case. In fact, the first film's cult wanted to burn Alessa because she was "sin incarnate" due to being born out of wedlock.

(2) At the end of the first movie, Sharon and Dark Alessa recombined to become a complete incarnation of Alessa, containing both sides of the soul and all of Alessa's memories and powers. In Revelation, Dark Alessa and Sharon are still in separate bodies, and no mention is made of Alessa's adult form at all, despite that she controlled everything that happened in the first film.

(3) In the first film's climax sequence, all of the remaining cultists are killed by Alessa and Dark Alessa, allowing Alessa to reunite into one body and leave the town knowing her revenge was complete. Revelation shows that there are still many cultists living in the alternate reality, walking around Alessa's world and even leaving their insane in the local asylum. It is not possible that Alessa did not know about this sect of the cult, and this makes all of the events in the first movie completely meaningless.