Inside (stylized as INSIDE) is a third-person puzzle-platformer adventure video game developed and published by Playdead. It was released on June 19, 2016 for Xbox One and July 7, 2016 for Microsoft Windows. Inside is considered a spiritual successor to Playdead's previous game, Limbo, which was initially released on July 21, 2010 on the Xbox 360 and later ported to other systems.
Inside is a puzzle platformer wherein the player controls a young boy who explores a surreal environment presented as a primarily monochromatic, 2.5D game. The player can make the boy walk, run, swim, climb and use objects in the environment to progress in the game. In certain sections, the boy gains the ability to control lifeless bodies to complete certain puzzles and later permanently gains this ability as well as the ability to breath underwater.
The boy character can die, including if some puzzles are not completed fast enough (such as being shot with a tranquilizer dart by hunters, caught by dogs, or drowning). As with Limbo, these deaths are accompanied by gruesome animations, and the game continues from the most recent checkpoint.
Among the environment are hidden rooms that contain lit orbs, which the player can deactivate. If all these are deactivated during a playthrough, the player can unlock the game's alternate ending.
The game starts with a nameless, red-shirted boy sliding down a rocky incline in a forest. While running through the forest, he encounters mysterious guards wearing masks, who are either inspecting the forest or are intent on chasing and/or killing the boy. After being chased by dogs and various guards who shoot at the boy, the boy finds himself in an abandoned farm where parasitic worms cause the farm's pigs to go rampant. The boy also has his first encounter with the mind-control mechanism of the game in the form of a puzzle.
Leaving the farm, the boy enters a city where lines of people are moved through mind control. A mistake lands the boy in the middle of a line of mind-controlled people, and he has to act in unison with the people around him to hide his identity. Unfortunately, he is forced to break his cover after a dog starts giving chase. After solving more puzzles, some involving mind control, the boy finds himself in a large underground factory where most of the rooms are flooded. The boy commandeers a pod-like miniature submarine and dives into the depths of the factory.
While the boy explores the flooded rooms, he encounters a humanoid, siren-like creature with long hair on several occasions. To progress, the boy must avoid the creature by shining his submarine's light onto it and trapping it to prevent it from following the submarine. Eventually, the boy exits the submarine and enters a mining facility where he must use mind-control to guide 19 bodies onto a pressure-pad; this allows the boy to proceed into a shock-wave atrium that emits a powerful force on the boy's surroundings. The boy passes through the atrium safely without being blasted away by the shock-wave, and enters a laboratory where scientists are performing underwater experiments on bodies.
The boy eventually comes across the underwater creature again, but this time it drowns the boy and attaches a device similar to the mind control helmets onto him. This allows the boy not only to utilize mind control without a helmet, but also to swim underwater without drowning. Continuing through the office/laboratories, the boy eventually sees many of the scientists running toward a large spherical container, which the boy finds a way into. Inside the chamber, the boy sees a large blob-like creature, made up of people's arms, legs, and heads, connected to four mind-control rods around the underwater container. After disconnecting them and freeing the blob, the boy is absorbed by the blob; the game's focus and the player's controls now are centered on the blob creature.
The creature escapes its confinement, going through various offices and work areas (some where the boy already passed though), killing some of the scientists in its path. Some scientists make attempts to capture or hinder the creature to no avail, while others help the creature try to escape. After luring the creature into a dark room, the creature is tricked and plunged into another tank, where the scientists look upon it before closing the hatch above. Escaping confinement again, the creature breaks through a wooden wall, rolls down a thick forest hill, and rests at a grassy coastline in a sunbeam. The game ends with the creature silently and motionlessly bathing in the sunlight.
If the player deactivates hidden light orbs found throughout the game in one playthrough, an alternate ending is unlocked. Underneath the cornfield at the start of the game, an underground bunker is found. Opening a large door will show the player a room where a mind control helmet is connected to various computers. If the boy unplugs a socket at the end of the room, the room will become dark and the boy will become limp like the controlled people seen earlier in the game.