Story

The Portal games are story driven games, as such the scenario takes an important place in the gaming experience.

In the games you play Chell, a young women stuck in an Aperture Science complex forced by the Artificial Intelligence GLaDOS to solve tests in specialy designed chambers using for solving them the Handheld Portal Device.

Portal & Portal: Still Alive
Portal and Portal: Still Alive have exactly the same story, Portal: Still Alive being the port of the original game on Xbox 360 Live Arcade, with only new advanced chambers imported from Portal: The Flash version (nothing story related).

The scenario of these games can be divided in two main acts, the first act in which Chell tries to solve test chambers and a second act where she escapes the testing area and tries to reach GLaDOS.

Act 1: The test chambers
In this act, Chell tries to solve 19 test chambers of increasing complexity and difficulty while GlaDOS watches and comments on her actions. The incentive for going through these chamber is the promise of a Cake at the end of the tests.

In the really beginning of the game Chell wakes up in the Relaxation Vault where an automatic message gives her a welcoming speech, then an orange portal opens and the tests begin. Chell starts without the ability to place portals then finds the Portal Gun allowing her to place only one blue portal before finaly getting the Dual handheld Portal Gun allowing her to place the two portals, blue and orange, where ever she wants (and can). Apart from this progression in portaling ability, each chamber progresses in complexity by adding a little mecanics or a new object that changes a bit the way to apprehend the chamber's environement. Those new objects include the Heavy Duty Super-Colliding Super Button, the Weighted Storage Cube (and later the Weighted Companion Cube), the Vital Apparatus Vent, the Material Emancipation Grill, the Victory Lift, the High Energy Pellet and the Unstationary Scaffold.

As the story progresses some special alcoves are found, presumably where Doug Rattmann was in hiding, with tags written on the walls with black chalk saying "The Cake is a Lie" (which became a meme afterward). This imnpression is made stronger by certain comment from GLaDOS that seems to point at a lie (for instance: [[Media:GLaDOS 14_part1_entry-2.wav|"The Enrichment Center is required to remind you that you will be baked [garbled] cake."]]).

When Chell reaches the end of test chamber 19, while on a Scaffold, GLaDOS reveals that the Scaffold is going into a furnace. Using the Portal Gun, you manage to escape from the fire, disorenting GLaDOS and starting you run in the corridors of Aperture Laboritories.

Act 2: The escape
After having escaped the furnace using portals, you start roaming in the backstage of the tests chambers and the Aperture complex, with GLaDOS telling you to come back at first, promising you cake and a party with all your friends. But the more you progress in the backstages of the laboritories the more GLaDOS become aggresive, placing turrets and rocket launching turrets to block your way and try to kill you. In the end you finaly reach, after multiple traps, a huge circular room where you met GLaDOS.

When you arrive in this room GLaDOS announces she's going to give you a surprise, but instead of it one of her core falls down which you can throw in the Emergency Intelligence Incinerator. At that moment GLaDOS voice gets less computerize, smoother, and she reveals that if we never encounter any human it was because she killed them all with neurotoxin, and start floading the room with neurotoxin, leaving you roughtly 5 minutes to live.

She activates a rocket launching turret that allows you, by redirecting missiles to detach the remaining cores off of GLaDOS and throw them in the incinerator too, detroying and killing her, and freeing you from the complex. You open your eyes after a white screen, in the middle of metalic pieces (with Hoopy the Hoop rolling), then a robot grabs you and pull you back, finishing the game.

Portal 2
Portal 2 was realeased simultaneously on PC & Mac, Xbox 360 and PS3 so the story is the same for each platforme.

Single Player
The narration in Portal 2 is completely differente, it introduces a clear separation in chapters (similar to the chapter in Half-Life), each chapter making the story progress. You still play Chell, equipped with the Portal gun, but the testing isn't a significative part of the story, not as much as in the original game, the story has more depth than simply testing.