The show calls itself a "social experiment" in determining the physical and mental endurance of the competitors.
The show's theme is based on solitary confinement; accordingly, the contestants are placed in isolated pods, with only an artificial intelligence named Val to communicate with. In reality, Val's voice is a computer-modified human voice. In season 1, Val was likely voiced by a male, whose voice was altered. In Season 2, Val is voiced by a female, with little computer modification. However, some "corruption" can be heard in the voice pattern where Val speaks a word or two in a similar voice to Season 1. In the recent rebroadcast of the Season 1 episodes, the producers have replaced the computer-sounding voice with the more feminine voice that was used in Season 2. In the Season 3 episode "Rest In Pieces," Val's "eye" turns red and its voice takes a deep, sonorous, distorted tone, similar to that of Jigsaw in Saw, while giving instructions for the episode's test. Val is possibly a reference to HAL, the demented computer who takes over the spaceship in 2001: A Space Odyssey. Val also bears a slight resemblance in tone and voice to the AI and main antagonist, GLaDOS, in the video game, Portal.
No contact with the outside world - or other competitors - is permitted, with the following exceptions:
* At the very beginning, a final two-minute phone call is permitted.
* The guests had a chance to send a letter to their loved ones (in Season 2, Val did not tell them to when given pen and paper)
* In Season 1:
* Twice, the guests were allowed to speak to each other, but only through Val.
* In Season 2:
* During the auction in Episode 4, another phone call was auctioned off.
* In Season 3:
* During the first episode, contestants were randomly paired 2 per pod for the first challenge.
* During the final episode. The last two contestants were allowed to talk smack to each other via Val.
Beyond the social isolation, there is also isolation from time, with no clocks, watches, or other timepieces available to contestants. There are no environmental time cues (sunlight or moonlight).
The environment is completely controlled, from temperature, light, access to a restroom, food, etc. In addition, the room is roughly octagonal, adding an additional disorienting aspect.
Players are only referred to by their number, not their name. This is an additional separation from the world, as their identity is reduced to a number. (This is similar to The Prisoner.)
A Season 1 episode revealed that alcohol was not permitted, but in season 3 one person got a plate of cheese and a glass of wine as a prize.