Trap Doors

A mechanical door built into the playfield surface that can open and close during play, transforming the geometry of the game mid-ball. When shut, the trap door is flush with the playfield and the ball rolls over it like any other surface. When triggered — by hitting a target, completing a sequence, or through game logic — the door swings open to reveal a hole, a ramp entrance, or a passage to a sub-playfield area. Williams’ Fun House (1956) featured trap doors that opened to become Gobble Holes, while Gottlieb’s Haunted House (1982) used them as secret passages between its three playfield levels. The element of surprise — a familiar surface suddenly becoming a hazard or an opportunity — makes trap doors one of pinball’s most theatrical mechanical features.