Portal 2 on PlayStation 3 takes place years after the events of its predecessor, Portal. At the end of the first game's single player campaign, the character you play as, Chell, is taken away by a robot and placed in stasis inside the walls of the Aperture Science facility for many years. Upon waking, she discovers that the entire place has descended into ruin.
Thankfully, she has a little help from the bumbling personality robot, Wheatley, and quickly escapes the confines of the room. Unfortunately, once she is out, she inadvertently resurrects a menacing artificially intelligent computer system called GLaDOS (Genetic Lifeform and Disk Operating System).
With GLaDOS in control of the entire facility once more, Chell is forced to embark on another series of mind-bending tests using her wits, Wheatley and the power of the portal gun she discovered in the first game.
This is where you come in. Good luck, because with GLaDOS after you, you're going to need it.