Leaven and Worth escape from Quentin who is now completely insane with anger. Together with Kazan's factorising ability, Worth manages to "solve the cube" and find the bridge. They reach the bridge just in time as it moves away towards the exit. They open the door into a dark red cube, the "exit cube." They step through and open the hatch to the outside. All that can be seen is a bright white light. Worth sits down, suddenly overtaken by depression, he exclaims that there is nothing for him to live for on the outside anyway. Leaven sits down next to him and tries to encourage him, but barely manages to do so, before being stabbed by Quentin who has followed them.
Quentin, covered in blood, attacks Worth, who yells at Kazan to run. Kazan in a panic manages to climb through the hatch just before Quentin beats Worth off and tries to climb through himself. With the last of his strength, Worth grabs Quentin's leg and hold him in the hatch. Because of this, Quentin is cut in half as the cube moves away from the exit and the entire cube begins the rotation again. Worth falls down next to Leaven's body, and presumably dies next to her. Kazan was the only one to escape the cube, and he finds himself in a short corridor. One end is lit brilliantly white. The film ends as Kazan walks into the light. The viewer can only wonder what was outside the cube and what its purpose was.