Portal storyline

This article describes the Portal storyline, chapter by chapter.

Portal is set in the Half-Life universe, and is presented to the player through the game's audio messages and visual elements seen throughout the game. Additional elements of the story's background are developed from the fictional Aperture Science website created by Valve for the game.

Testchamber 00


At the start of the game, Chell wakes from a stasis bed, though how she came to be there is initially unknown. She wakes up wearing heel springs: these allow her to fall long distances without injuring herself. GLaDOS informs her of the test and proceeds to guide her through the introductory Test Chambers. At this time Chell lacks the Aperture Science Handheld Portal Device altogether.

The game starts with Chell waking up in a small glass room. There is a bed and a small table in the room, and the table has a coffee cup, clipboard and radio on it. About 20 seconds later a voice, which is later learned to be GLaDOS, the AI of the complex, begins speaking. Chell learns that she is in the Aperture Science Computer Aided Enrichment Center, and that the room she is in is called a relaxation vault. The phrase "your specimen has been processed," as spoken by GLaDOS, suggests that the player is a test subject, and as exploited by third party map makers, Chell may be a clone.

At the end of the GLaDOS's countdown, a blue portal in the wall opens. Through it, the player can see into an orange portal in another wall, giving the player a chance to see Chell in game. Continuing through a corridor leads Chell to a small chamber. When Chell enters the chamber a door closes behind her. In this chamber is a button and a storage cube; this mechanic is used in many later levels.

At the end of the chamber is an elevator, also used in later levels.

Initially the test chambers were clean, friendly environments. Chell is promised cake and grief counseling as a reward for successfully completing the tests, and this appears as an available, but deactivated, component in the stage descriptions. However, as Chell works through the stages, GLaDOS's colorful dialogue begins to paint an unnerving picture of the type of research that occurs in the facility. She cheerfully informs Chell of various safety risks in each stage that could kill or seriously injure her. Glass walls in key areas of the stages allow observation of the subject by laboratory personnel, but the chairs are empty and no research personnel are seen. Some stages are broken, allowing Chell to explore behind the pristine test areas and into grimy areas which resemble a derelict factory. Prominent in these areas is graffiti from an unknown benefactor (Presumably the Rat Man, as stated in the commentary) accusing GLaDOS of lying about the nature of the tests, and repeatedly claiming "the cake is a lie". GLaDOS becomes uncomfortable with Chell exploring these areas and begins to hint that she is ultimately disposable and will be dealt with. Such areas contain hints that Aperture Labs is in competition for GSA funding with the Black Mesa Research Facility, from the first Half-Life game.

Trivia

 * The radio inside of Chell's chamber plays an instrumental salsa mix of "Still Alive".
 * The portal was deliberately introduced in this stage, to confirm that the portal leads to another location on the same planet, rather than another dimension.

Test Chamber 01


Here the player reviews how to use buttons, storage cubes, and portals. This level is designed to firmly establish the mechanics of the Portal Device in the player's mind, so that they would be familiar with the basic concept of the game.

Test Chamber 02


As the tests progress she eventually acquires the first "portion" of the Aperture Science Handheld Portal Device, allowing her to place blue portals but not orange ones.

Test Chamber 03


Chell must enter through an orange portal to reach the other side of a gap.

Test Chamber 04


More buttons and boxes.

Test Chamber 05


This time, there are two boxes and two buttons. GLaDOS starts revealing her evil side when she says that "our previous statement suggesting that we would not monitor this chamber was an outright fabrication."

Test Chamber 06


Here, the Aperture Science High Energy Pellet is introduced.

Test Chamber 07


More energy balls, also moving platforms are introduced.

Test Chamber 08


Acid pits are introduced, in combination with moving platforms and energy balls.

Test Chamber 09


A so called "impossible" test chamber, with buttons and cubes used.

Trivia
Later in the game, this chamber is used as part of a "behind the scenes" area.

Easter Egg: If perched on the platform just right, the player can get a blue portal past the trigger for the elevator, and can fall to the bottom of the shaft.

Test Chamber 10


A new concept is introduced: flinging. As GLaDOS says: "Momentum, a function of mass and velocity, is conserved between portals. In layman's terms, speedy thing goes in, speedy thing comes out."

Test Chamber 11


Chell acquires an upgrade that allows her to place orange portals.

Test Chamber 12


More flinging. GLaDOS also reveals herself to be more emotional than most people think, by the phrase "Weeeeeeeeeeeeeee--" at the end of it.

Test Chamber 13


The first real challenge. Combines buttons, boxes, energy balls and moving platforms. The previous stages were constructed to introduce the basic concepts of Portal in small, easily-understood segments, and this stage collects them into one place as a sort of 'final review'.

Test Chamber 14


Another challenge. Combines buttons, boxes, energy balls, moving platforms (moving vertically in this case) and acid pits.

Test Chamber 15


A very long chamber with all of the above included.

Test Chamber 16


"Due to mandatory scheduled maintenance, the appropriate chamber for this testing sequence is currently unavailable. It has been replaced with a live-fire course designed for military androids. The enrichment center apologizes for the inconvenience and wishes you the best of luck."

This level introduces turrets, three foot tall gun-toting tripods that speak cute phrases when they see a target or are tipped over.

Also, hints are given in behind-the-scenes areas that the player wasn't the only test subject to go there, so the chamber may be in its proper place after all.

At the end of the chamber, the character might realize that GLaDOS does not control everything all the time. A recording tells androids that "Android Hell is a real place where you will be sent at the first sign of defiance."

Test Chamber 17


Noteable because of the appearance of another character: the companion cube. At the end of the chamber, Chell is forced to "euthanize," or more bluntly, incinerate the companion cube.

Trivia: In the developer commentary, the player learns that the chamber was actually originally a long level called the "cube run," where players would take the cube through a number of challenges. Apparently however, playtesters would leave the cube behind, so they stuck a heart on it and had the AI keep on talking about it.

Test Chamber 18


By far the hardest chamber. Turrets reappear here. At the end, GLaDOS says that "the next test requires exposure to uninsulated electrical parts, that may be dangerous under certain conditions," which comes into importance later.

Test Chamber 19


The last chamber. A simple energy ball trick is required, then the player must get on a moving platform, and dodge a number of obstacles. At the last stretch, a sign signalling cake points around a corner. As the platform rounds the corner, that the platform is leading the player into a large fire pit. Using portals, Chell can escape. From then on, Chell is inside the unseen innards of the facility with occasional hints that suggest that, again, someone has done this before.

Escape


After the final test, Chell is "sent to receive her cake", but is plunged into a furnace (to "be baked," as GLaDOS had accidentally admitted numerous previous times, with glitches resembling Freudian slips). She manages to escape into a maintenance area and GLaDOS begins to show agitation, claiming first that it was the real final test, and then that it was just a joke. She tells Chell that there will be a party held in her honor and urges her to "assume the party-escort submission position" on the floor. Chell flees into the facility's numerous maintenance corridors, and GLaDOS becomes increasingly agitated. Roughly the second half of the game continues behind the walls of previous stages and the inner laboratories of Aperture Labs as Chell follows eerie notes written on walls and uses the Portal Gun to work her way upward to the top of the facility. Finally, Chell confronts GLaDOS, a large machine hanging in a cylindrical shaft. (Near the entrance to the room is a desk with a red phone. The developers stated that there was someone stationed at the red phone in case GLaDOS showed signs of independent thought - apparently, they weren't fast enough to make the call as the wires were cut.) As Chell destroys critical components of the machine, GLaDOS's personality degenerates. During this confrontation, GLaDOS makes several comments that something has gone wrong in the outside world, and that she is the only thing keeping the facility from "them", which many think might be referring to the Portal Storms or the Combine of the Half-Life universe. When GLaDOS is completely destroyed, the facility begins to shake and fall apart, and Chell is lifted high into the shaft, blacking out. She wakes on a pile of debris during the light of day behind the fence of Aperture Labs.

The final cutscene zooms up and through various areas of the Enrichment Center, depicting Chell's escape from certain death and her journey through the maintenance areas and empty, decaying offices of the Aperture Science Enrichment Center.

The final scene of the game (after the credits have rolled) shows the promised cake surrounded by various metallic glowing orange spheres similar to those that were installed in GLaDOS. Some of the eyes activate and a robotic arm puts the candle out. The credits roll as GLaDOS gives a concluding report about Chell in the form of the song "Still Alive" by Jonathan Coulton. It reveals that GLaDOS enjoys the companionship of the test subjects and that it felt a particular fondness for Chell. Although it is uncertain, the song implies that Chell has survived by lines referring to her in the future tense (the song also reveals that GLaDOS is still active- the objects in the warehouse with the cake are not only eyes, they are components of GLaDOS' AI).

When the ending credits and song end, the player is greeted with a new background: a cake with lit candles on a desk next to a radio on a table as well as the same red phone (which has its buttons shaped like the Aperture logo). If the background is left alone for long enough, it eventually pans to show the Companion Cube on the floor to the right side of the desk.

Trivia

 * This section of the game does not bear any official title. "Escape" is the map prefix.
 * Via the  command, it is possible to go to the area outside Aperture Laboratories where the remains of GLaDOS can already be found, as well as the warehouse where the cake is located.