One-Way Entrance

And consider this dismaying observation: this chamber has no windows, and no doors. Which offers you this chilling challenge: to find a way out.

—Disney's Haunted Mansion ride

If the protagonists go into a haunted building, there is a non-zero chance that while their back is turned the walls and doors will turn into hole-less walls, leaving the unfortunate protagonists trapped inside.

A less (but probably still) supernatural variant is for the doors to slam shut behind them and refuse to open.

See also: Locked in a Room and It Was Here, I Swear. Compare Mobile Maze

Examples of One-Way Entrance include:

Flat-Out Gone

Live-Action Television

• In Buffy the Vampire Slayer episode, "Fear Itself", Anya arrives at the Halloween Party. But she can't enter because the front door disappears!

Amusement Park Rides

• This is part of the story of The Haunted Mansion attraction at the Disney Theme Parks.

Video Games

• The Evil Within 2: When Sebastian enters a new hallway, the blood-stained door vanishes!
• In Layers of Fear, Episode 3, behind one of the doors is a wall that has a chain, but upon entering this room another door disappears.

Western Animation

• Samurai Jack and the Haunted House.
• Doug: While at a haunted house ride, the floor in the main lobby/living room begins to recede into the walls.

Other Media

• The creepypasta The Door Game has the front door disappearing and replaced by a wall, which one of the players points out. Later on as the game progresses, it got worse.

Slammed Shut and Locked/Jammed

Films

• In the film Winchester: The House That Ghosts Built, there are doors shutting by themselves and whatnot.
• Paranormal Activity, the open door to the bedroom where our heroes are sleeping slams shut. Micah jumps out of bed yelling "F***!"
• In Stay Alive, when Miller goes to the basement, the door slams shut and separates him from his friends.

Western Animation

• In Gravity Falls episode "The Inconveniencing", the doors slam shut after the group tries to leave.
• In The Magic School Bus episode, aptly named "In the Haunted House", the door to the Sound Museum slammed shut after when all of the class went inside the mansion.

Video Games

• Wales Interactive's indie game, Don't Knock Twice, uses this trope as part of a game mechanic, where the doors closes when the player has fully inspected rooms and leaves them.
• In DreadOut the door slams shut on the player, and the only way out is to find the key.
• In one room of the catacombs at King's Quest VI, the two doors slam shut and the ceiling starts to descend on Prince Alexander, until the puzzle is solved.
• In Yomawari: Midnight Shadows, the door closes on Yui when she tries to exit a room after awakening in a crumbling building.

Real Life

• Chicago's "Murder Castle", built by serial killer H. H. Holmes, was deliberately designed to confuse and entrap his guests, with secret passages, fake walls, and hidden rooms, and this trope in abundance.

Unsorted, Ambiguous, and Other

Tabletop Games

• Considering the game's genre, and that you can't just leave through the front door of the titular "House on the Hill" in Betrayal at House on the Hill, this trope is clearly in play.

Video Games

• In The Witcher 3: Wild Hunt, one of Geralt's contracts has an haunted old mansion. If Geralt enters the house, it starts to shake and the doors slam shut.

Western Animation

• In the DuckTales (2017) episode, "The Impossible Summit of Mt. Neverrest!", Scrooge, two of his nephews and Webby go into a cave for shelter and find the entrance sealed with a boulder.