Portal 2 - Plot - Single-player Campaign

Single-player Campaign

Chell wakes to find herself in a stasis chamber modeled after a motel room. An announcer's voice guides her through a cognitive test before she is put back to sleep. When she awakens again, many years have passed and the Aperture Science facility has become dilapidated and overgrown. Wheatley (Stephen Merchant), a personality core, moves the room—located in one of hundreds of shipping containers in a large warehouse—and the pair attempt to escape via the test chambers. In the process, they discover the dormant GLaDOS (Ellen McLain) and accidentally reactivate her. GLaDOS, who has not forgiven Chell for murdering her, separates Chell from Wheatley and then begins rebuilding the facility.

GLaDOS begins testing Chell in a series of new test chambers until Wheatley helps Chell to escape. The pair sabotage the turret and neurotoxin manufacturing plants before confronting GLaDOS. Chell performs a "core transfer", replacing GLaDOS with Wheatley in the hardware that controls the facility. Wheatley quickly becomes intoxicated with power and places GLaDOS's personality into a module powered by a potato battery. GLaDOS then claims to remember Wheatley's original purpose; she claims that he is an "intelligence dampening sphere" that was originally designed to be "the dumbest moron who ever lived", producing illogical thoughts to hamper GLaDOS's decision-making processes in an attempt to make her less dangerous. Wheatley angrily denies this and throws Chell and GLaDOS into an elevator shaft that leads to an abandoned area of the facility, miles underground.

After they have landed, GLaDOS is abducted by a bird while Chell explores the decommissioned section of the facility from where she ascends through a series of old test chambers in chronological order, the decor slowly changing from 1950s styles to one similar to that is seen early in the game. As she navigates the chambers, Chell regularly receives audio recordings of Aperture Science's CEO, Cave Johnson (J. K. Simmons). The player learns that Johnson became increasingly embittered and deranged as his company lost money and prestige, which led to him being fatally poisoned by moon dust. His assistant Caroline (McLain) became a test subject for a mind-to-computer transfer experiment, and ultimately became the model for GLaDOS. Chell reunites with GLaDOS, and the two form a reluctant partnership to stop Wheatley before his incompetence causes the reactors to fail and destroy the facility. As they make their way through the old test chambers, GLaDOS struggles with the revelation about Caroline.

Chell and GLaDOS return to the modern facility and face Wheatley, who is driven by GLaDOS's old hardware to continue to test them. Wheatley tricks Chell into a series of deathtraps. Chell escapes because of Wheatley's clumsiness and lack of logical thinking, and makes her way to his chamber. In their final confrontation, Chell attaches three corrupted personality cores (Nolan North) to the body that Wheatley inhabits, allowing GLaDOS to initiate a second core transfer and put herself back in control. Just as Chell is about to conclude the core transfer, Wheatley reveals that he has booby-trapped the process. With the facility's reactor on the brink of meltdown, the roof collapses, revealing the night sky. Chell shoots a portal at the moon overhead, causing the vacuum of space to pull her and Wheatley through the other portal still inside the chamber. GLaDOS pulls Chell back inside, where she falls unconscious, leaving Wheatley stranded in space with a corrupt, space-obsessed personality core.

When Chell awakens, GLaDOS says that she learned valuable lessons about humanity from her Caroline personality. She promptly deletes this aspect of her personality and reverts to her usual antagonistic attitude. She finally allows Chell to leave the facility and says that trying to harm Chell has proven so difficult that she has chosen to let her go. Chell is taken to the surface and, after a brief opera, containing the turrets singing a song entitled "Cara Mia Addio", enters a wheat field from a corrugated metal shed. The charred and battered Weighted Companion Cube, supposedly incinerated during the events of Portal, is thrown through the door after her before the door slams shut. In the epilogue, Wheatley floats helplessly through space and expresses regrets about betraying Chell.