|“|| This must be what Hell is like...
Walter Sullivan's Otherworlds are a series of connected "Otherworlds" in Silent Hill 4: The Room. The protagonist, Henry Townshend, finds a mysterious hole in his apartment room's bathroom that leads to several of these worlds. In these worlds, he encounters a variety of monsters and ghosts, most of which pursue him.
The hole leading to these worlds stays in his bathroom for the first half of the game. However, after finishing the Apartment World, the player has to make their own hole using plates they found throughout the first half of the worlds. The hole is in Henry's laundry room for the rest of the game.
In the second half of the game, each Otherworld is connected by a foggy spiral staircase that Henry and Eileen Galvin must reach the bottom of. This staircase is full of strange things, such as human limbs and figures. There is a bloody trail leading down the staircase, only stopping at the very bottom. Also, the fog that engulfs the staircase lessens in thickness as Henry and Eileen travel down further.
The revisited Otherworlds Henry and Eileen visit via the spiral staircase are, for the most part, the same as before, except each victim is now a ghost that can be deadly to Henry's health. There are also five Swords of Obedience, an item that allows Henry to keep a ghost pinned once it is knocked down.
At the bottom of the spiral staircase is a dark abyss containing Room 302 of the Past.
- Main article: South Ashfield Station
The first Otherworld Henry visits is the Subway World, the South Ashfield Station located near his apartment. In this world, the player must navigate through a series of empty hallways and subways in order to complete the world and move on to the next. Henry wakes up sitting on a long, descending escalator. A few moments later, he meets Cynthia Velasquez, a woman who believes she is dreaming and offers Henry a "special favor" if he helps her find a way out. Cynthia soon feels as if she is about to vomit and runs into a nearby restroom, leaving Henry alone.
After waiting patiently for Cynthia to come back, he realizes Cynthia has disappeared and meets the first monster of the game, the Sniffer Dog. Henry enters the bathroom Cynthia disappeared in, but all of the stalls are empty. After going through a hole in the bathroom and returning to Room 302, Henry gets a phone call from Cynthia, who needs his help and tells him she has a token he can use to progress further.
Upon returning to the subway bathroom, Henry finds a statue that is very similar to Cynthia holding subway tokens. Henry eventually reunites with Cynthia after helping her out of a locked subway train. She follows Henry, but disappears again when Henry finds an exit. Her voice calls out to Henry over a public address system, vaguely telling him about a discovery she has made. However, Cynthia screams as Walter Sullivan attacks her. When Henry reaches Cynthia, she is dying with "16/21" carved into her chest. He stays with her through her last moments.
- In this world, a large, worm-like creature can be seen entering and exiting holes. It symbolizes Walter Sullivan's umbilical cord, and it reappears in the other worlds.
- If Henry walks into the men's or women's bathroom, a sound similar to a wooden or plastic stick is heard falling.
- There are also advertisement posters from Hazel Street Station in Silent Hill 3, such as "Havoc's Business Daily".
Henry meets the victim Cynthia Velasquez, who has long, flowing black hair that covers her face. By revisiting Cynthia's murder location, he finds a train handle that he uses to move a train on King's Street Line Platform where he finds the exit from Subway World. At the end of Subway World, Walter Sullivan starts stalking Henry and Eileen.
- Main article: Silent Hill Woods
The second Otherworld Henry visits is the Forest World, a forest located outside of Silent Hill. He meets Jasper Gein, a man who has a fondness for chocolate, sitting beside a large rock. Henry exchanges the chocolate milk in his refrigerator for a spade from Jasper. He uses the spade to dig underneath tree roots shaped like arms and finds a key that opens the door to the Wish House, an orphanage that taught children about the beliefs of the Order. Henry also has a brief encounter with Walter Sullivan as a young child instead of an adult. When Henry enters the Wish House, he finds Jasper, who has been set on fire, with "17/21" carved on his chest. Jasper slowly burns to death, telling Henry that he has finally met the "Devil".
- The key that Henry obtains will force Henry to enter the same area of the forest over and over again if the player does not put it in the box in his apartment.
Henry meets the victim Jasper Gein, who is on fire and holds a chalice. While exploring this world, Henry realizes Walter Sullivan is pursuing him and Eileen. He discovers that the Wish House Orphanage has been burned down, and a doll that is missing its limbs is sitting on a wheelchair in the burnt remains. Henry also has another brief encounter with the child Walter. After Henry finds the doll's missing limbs in various wells, the doll moves its wheelchair, and Henry and Eileen find an exit underneath.
Water Prison World
- Main article: Water Prison
The third Otherworld Henry visits is the Water Prison World, a cylindrical prison located in Toluca Lake. The player must navigate through cells, some of which contain holes (or, as later perceived, corpse disposal chutes) that are used for unlocking certain cells on lower floors. Henry explores the Water Prison and discovers that the prisoners were always being watched as the locks to their cell doors deteriorated. Many prisoners were children taken from the orphanage and ended up being starved to death.
He meets Andrew DeSalvo, a guard who used to work at the prison and abused the children. Henry frees Andrew from his locked prison cell, and the two have a brief encounter with the child Walter Sullivan. Andrew warns Henry of the child's mental state and runs off. Henry makes his way beyond a kitchen door by inputting the four-digit code "0302", coincidentally the same number as his apartment room. There, he finds Andrew DeSalvo floating in water, having been apparently drowned by Walter Sullivan. Andrew has "18/21" carved into his stomach.
Henry meets the victim Andrew DeSalvo, who is shirtless and holds a key that is required to move on. Henry pins Andrew down with a Sword of Obedience, takes the key he holds, and unlocks an underground exit.
The fourth Otherworld Henry visits is the Building World, a twisted version of Ashfield and some of its buildings including the hotel that Henry can view from his bedroom window. The maps are complex and contain many floors, the level of basements reaching an astonishing number of twenty-three. It is in this world that Henry finds his first Sword of Obedience.
He also meets Richard Braintree, a resident of his apartment building who lives directly across from him, only a floor below. Instead of following Henry, Richard decides to escape the world on his own. As Henry enters and descends through an elevator, he sees Richard, who has recognized a young Walter Sullivan from South Ashfield Heights and is chasing after him. Henry makes his way to a large staircase when he suddenly hears Richard's scream. When Henry reaches the top of the staircase, he finds a replica of Room 207, Richard's apartment room. He enters and finds Richard being electrocuted in an electric chair, "19/21" carved in his forehead. Nearby, the child Walter points outside a window (possibly at Henry's next-door neighbor) and disappears into thin air. Henry tries to help Richard, but is unable to free him and watches him die.
- At the very beginning of the area, when Henry walks down the long passageway, Gum Heads can be seen jumping across the buildings if the player tilts the camera up.
- If the player attempts to call the phone number listed on the building's billboard from his apartment, disturbing noises and loud groaning are heard.
Henry meets the victim Richard Braintree, who has the ability to teleport. He finds a memo about a person who writes about their "memories" — four reminiscences that need to be found and put back in their original place. Once Henry returns the four reminiscences, a clock chimes and leads Henry and Eileen to a boss fight with The One Truth. After the boss fight, a door unlocks, and Henry and Eileen make their exit. Walter Sullivan only appears in a cutscene near the beginning of this revisited Otherworld. Older Sullivan and younger Sullivan encounter each other, and the older kidnaps himself, telling him things about their mother and how they will have her.
- After Henry reads an article about the pet shop describing a murder, sounds of a gun shooting and animals' crying out can be heard. If Henry decides to re-enter the pet shop, the aisles will be knocked over, bullet holes will be in the walls, and he will encounter the pet shop owner's ghost. 
- If Henry doesn't pin down Cynthia and/or Jasper in any of the previous worlds, Cynthia will appear after Henry overhears the two Walters talking, as well as in Garland's, and both will appear in the area with numerous locked doors.
- A major glitch here allows the player to skip the four reminiscences sidequest. It requires putting Eileen near a wall, running into her, and then running quickly into an elevator, leaving her behind. After heading in the direction of the wheelchair room area, Eileen will come and follow Henry, having apparently walked through the fence.
- Main article: South Ashfield Heights
The fifth Otherworld is South Ashfield Heights, Henry's own apartment building. The alternate South Ashfield Heights is covered with rust, chains, and walls that seem to pulse and bleed. Henry sees Walter Sullivan, this time as an adult, knocking on Eileen Galvin's apartment door. Henry wonders if the next victim this time is Walter or his own neighbor Eileen. He later hears her being painfully beaten by Walter whenever he passes by her door.
After he finishes exploring the alternate apartment building, Henry finds a key in his own room that unlocks Eileen's door. Inside, he finds child Walter standing in front of Eileen, who is severely injured and bleeding from the adult Walter's assault. Eileen thanks the child for protecting her from his older self and appears to die in front of Henry.
Walter Sullivan makes brief appearances, trying to shoot Henry with his gun. This is the first part of the game where Henry has the option of leaving his apartment through the front door. After examining five hanging bodies (that represent Walter's parents), Henry unlocks Frank Sunderland's (the superintendent of South Ashfield Heights) apartment room. Inside, he discovers Walter's umbilical cord, which Sunderland has kept in a box for years. Henry suddenly sees flashes of Walter's memory in his mind and falls to the floor with a massive headache. Eileen tries to comfort Henry and decides to find the young Walter on her own, and they separate.
- A woman can often be heard sobbing in several of the rooms and hallways. These are speculated to be the sounds of a woman in labor. The woman is first heard in Room 301, but when going down the apartment's staircase into Room 201, the cries suddenly vanish, making the source impossible to find.
- Henry can examine two pictures that were apparently drawn by little Walter: one may represent Walter's father, and the other is of a woman being torn apart by the Death Machine, which may represent his mother.
- On the third floor staircase, a woman can be heard crying. Her voice sounds similar to Eileen.
- There are six different cutscenes the player can receive depending on Eileen's current health condition (fine, partially possessed, and possessed). The two cutscenes are when Henry finds Eileen with Walter's sketchbook and when Henry examines the umbilical cord in Frank Sunderland's room.
- Main article: St. Jerome's Hospital
The sixth Otherworld is the Hospital World, an alternate St. Jerome's Hospital. Henry wakes up and briefly encounters Walter, who appears to be using surgical instruments on a female body's womb. Henry then flees from the room and discovers Eileen's purse on the floor. He also discovers numerous x-ray pictures of Eileen's body.
By using a key found in one of the hospital rooms, Henry unlocks Eileen's hospital room door and finds her sleeping on a bed. She suddenly wakes up very startled and doesn't believe Henry when he talks about his experiences. She then remembers her assault by Walter and apologizes. Henry and Eileen decide to stay together and try to find a way out.
He takes her to a hole and realizes that Eileen isn't in his apartment when he wakes up. He then returns and reunites with Eileen, realizing that he is the only one who can use these holes. Eileen tells Henry about Joseph Schreiber, a journalist who disappeared six months before Henry moved into Room 302. Like Henry, Joseph became trapped in Room 302. Henry and Eileen decide to "go down into the deepest part of him and look for the ultimate truth".
- The body that Walter is dissecting in St. Jerome's Hospital has a close resemblance to Claudia Wolf; however, this is most likely a coincidence.
- The Hospital World contains a hallway leading to many strange rooms. The locations of these rooms are random every game. Some examples of these strange rooms are a room with a wheelchair with a moving shadow, a room with a spiked ceiling that falls down, and a room with Eileen Galvin's head.
Room 302 of the Past
- Main article: Room 302 of the Past
This Otherworld is visited just before Henry revisits the Apartment World. Because the second Apartment World isn't visited through the hole, the hole leads to Room 302 of the Past instead. It is in this room that Henry meets the first victim with good intentions: the ghost of Joseph Schreiber, the fifteenth victim of Walter Sullivan. He warns Henry and Eileen about Walter. In Room 302 of the Past, the red typewriter is present, which indicates that this is actually Joseph's room. There are candles everywhere on the floor, and there is a dent in the wall, presumably placed by Joseph himself, between the bedroom and the bathroom.
|“|| The plan was for the Otherworld to be a world that Walter had created, and that Henry, from Room 302, would get caught up in it. By “a world that Walter had created,” I mean that it’s made up of the things that had left an impression on him in his life…the things he perceives in his mind, so the stages are formed out of the places Walter has been and fragments of his memory.
|“|| The creatures are manifestations of things from Walter’s subconscious mind, and the ghosts are the people who Walter has killed, trapped in this world and wandering about. So to the murder victims, Walter’s world is this hazy, indistinct realm that they don’t yet really understand, which is why they break through walls, etc.
|“|| You can look out your window and such from Room 302, but there’s absolutely no intervention from outside, no interaction. That’s part of the “fear of isolation” that I think is new for this installment - the idea that, ultimately, you’re all on your own. And so this time, the protagonist is a unilateral victim, right - just in the worst possible circumstances. Every time he goes to the Otherworld, he’s attacked by these restless souls, and he doesn’t even know what’s happening with his own situation, yet this impending doom just keeps bearing down upon him - so there’s also that fear, I think.