A woman--known only as the "PLAYER"--is in an undisclosed location... possibly a warehouse. It's a single large room, with a table in the center and two chairs. In the chair across the table from her is the "GAME MASTER"-- a young man who has been enlisted by a shadowy organization to help run this game.
In the game, 20 players are in 20 separate locations, with 20 Game Masters. Web cams are arranged in each location to send video of each player to a clearing house, who coordinates it all into an underground betting pool, where elite, wealthy spectators can watch and gamble on the results. The Game Master is in constant contact with the main hub via a Bluetooth device, and he relays the results of each round to the Player.
The first round is simple--the Player must hold her hand over a candle flame until three of her opponents drop out. She makes it through this painful act, only to discover that each subsequent round will have worse, more painful challenges to endure-- cutting, drowning, and more. The woman is playing the game as a last resort to raise money for her daughter. The Player has lived a life of bad decisions, and this is her final effort to atone for her failures and do what's right for her child, so she's prepared to withstand the pain.
As she plays the game, her only confidante is the Game Master. He seems to be on her side, helping her keep it together mentally and emotionally as the pain takes its toll. He is an ally, doing what he can to ensure that she doesn't quit, and she begins to trust and rely on him. But as the rounds get progressively more terrifying, his true motives for running the game become clear-- he is a man who relishes the power the game gives him, and he doesn't mind her knowing as he begins to abuse his power.
The Player makes it to the final round, where she must engage in a game of Russian Roulette. She begins to understand that the Game Master doesn't intend for her to win -- never did. In the end, she realizes she's been manipulated in life, much the same as she's allowed herself to be controlled in the game. Instead of giving in to that fate, she takes her life back in her own hands, by turning the weapons of the game against the Game Master. She violently overcomes her oppressor, winning her freedom and the prize... and most importantly, a chance at a better life.