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.

Test Chamber 00


Chell wakes up in a so-called Relaxation Vault - with only a small table with a mug, radio, and clipboard listing test chamber hazards, as well as a toilet and a stasis bed of some kind - and is welcomed "again" by a Computerized Voice which states that "her specimen has been processed" and that "we are now ready to begin the test proper."

Chell then proceeds through the first area, and is introduced to Buttons, Cubes, and the Vital Apparatus Vents, as well as the Material Emancipation Grills.

It is possible to lock your self in this room, and GLaDOS will do nothing to help. To do this you need to put the Aperture Science Weighted Storage Cube next to the sign that is beside the door. Next, you jump on the sign and put the Aperture Science Weighted Storage Cube on the camera, jump off and you're stuck.

Throughout the early stages of the game, the voice only refers to "us" or "we," never saying "I," as though it were speaking for the Enrichment Center's long gone employees as a whole. This comes into significance in the later levels, when the entity seems to display more independent activity.

Trivia

 * The radio inside of Chell's chamber plays an instrumental version of "Still Alive."
 * During the verbal introduction, GLaDOS inexplicably blurts a bad Spanish phrase which roughly translates as "Please refrain from failing. Thank you very much for failing. Thank you." The meaning behind this doesn't seem comprehensible.

Behind the scenes

 * The portal was deliberately introduced in this stage in a way that confirms that they lead to another location on the same planet, rather than another universe, as established in Developer Commentary.

Test Chamber 01


Here the player reviews how to use buttons, storage cubes, and portals.

Behind the scenes

 * 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.
 * When the test chamber reappears in Portal 2, the portal are opens using buttons rather than generating automatically.

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


A simple puzzle using the newly acquired portal gun.

Behind the scenes

 * This level was intentionally designed to ensure players realize that both portals can be used as entrances and exits.

Test Chamber 04


More buttons and boxes. At the end of the chamber, GLaDOS states that the next test chamber will not be monitored, as "part of a required test protocol."

Test Chamber 05


This time, there are two boxes and two buttons. GLaDOS reveals that "our previous statement suggesting that we would not monitor this chamber was an outright fabrication." This begins to hint at her malicious behavior. She then says that "We will stop enhancing the truth, in 3, 2 -" but is cut off before she can finish, effectively nullifying the statement.

Trivia

 * It is possible, in both Portal and Portal 2, to get trapped in this chamber. This is accomplished by finishing the puzzle and shooting a portal into the next room, then stacking the cubes and camera to reach the orange portal, and throwing a cube into there. If the player then reshoots a blue portal, they are now trapped, as there is a closed door with no way to open it (a cube is now behind the door), and no portals on the other side. This will cause GLaDOS to scold Chell for her misbehavior with a line she uses in the post-escape levels.


 * If done in Portal 2, both cubes are "fizzled" as soon as one cube enters the portal and the Announcer congratulates Chell for trapping herself before opening the door.

Test Chamber 06


Here, the Aperture Science High Energy Pellet is introduced. Also introduced are brown walls that do not allow portal creation on them that are seen throughout many of the following test chambers.

Test Chamber 07


More energy balls, also moving platforms known as "unstationary scaffolds" are introduced.

Test Chamber 08


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

Behind the scenes

 * This was to be the first test chamber to feature energy balls. This chamber was shown to introduce too many new concepts at once and players were often frustrated. So the two preceding simpler test chambers were inserted before this one to introduce the energy ball puzzles more gradually.

Test Chamber 09


A so called "impossible" test chamber, with buttons and cubes used. In this chamber, the player is not able to do the test so easily because before in the tests, the Emancipation Grills were only found outside of the test after completing it, but now they are used during testing and now players will find out that portals close when you go through the Grill.

Trivia

 * Later in the game, this chamber is revisited illicitly, and must be solved in a different way, as the cube is no longer available. As well as having access to both sets of portals (instead of blue-only originally)
 * Another way to solve the test chamber with dual portal gun is placed over a piece of the dispenser through a portal

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."

Behind the scenes

 * The concept of flinging was one of the hardest concept for the developers to convey, and so this test chamber went through more iterations than almost any of the other test chambers.

Test Chamber 11


Chell acquires the full Aperture Science Handheld Portal Device that allows her to place orange portals as well.

Test Chamber 12


More flinging, now with more freedom allowed by the upgraded device.

Behind the scenes

 * This chamber was designed to retrain the player in using the fling maneuver, now that players could manufacture two portals at once.

Test Chamber 13


The first real challenge. Combines buttons, boxes, energy balls and moving platforms.

Trivia

 * A line from GLaDOS partly foreshadows her murderous intent. After reminding you that she can no longer lie to Chell and rather than stating that anything important happens at the end of the experiment, such as her being released or rewarded, GLaDOS simply says, "When the testing is over, you will be...missed." (Though the phrase could at first be interpreted in a lighter sense.)

Behind the scenes

 * 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.

Trivia

 * This chamber can be completed without even leaving the first room, thus omitting most of the level. The shortcut was originally unintentional, but after a playtester found it, Valve decided to leave it in, because it was just as difficult to figure out as the proper solution. They then added it as a challenge, requiring you to complete the chamber using only 2 portals to get the Gold, which is impossible while using the ‘fair’ way. To do this, you must first place a portal on the floor next to the Victory Lift, then ascend the stairs on your left. At the top, turn around and look down. When the stairs have fully retracted again, fire the other portal onto the surface the stairs form. Jump down and you will emerge through the portal by the lift. This may require several tries, as it is often hard to turn around and land on the lift itself, due to the fact that the first portal will most likely make you emerge facing away from it. To get around this, if you stand under the victory lift and shoot the portal in the same place, it will now be effectively upside-down causing you to be propelled in the correct direction. Once you are on, simply walk through the grill and into the elevator.

Test Chamber 15


A quick but also very difficult test. It involves the use of the Emancipation Grill that have been seen previously in Test Chamber 09 and are seen again in this Chamber. the player must solve it now that they are fully aware of the Grill's abilities.

This is the very first time a reward is mentioned: "Cake and grief counseling will be available at the conclusion of the test."

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 shoot when they see a target or are tipped over.

The player finds the first Ratman den, hinting at the reality of the tests, as well as the fact that there possibly are other people still trapped in the building.

GLaDOS stays true to her guise as a prerecorded voice by telling an "android" that "android hell is a real place where you will be sent at the first sign of defiance."

Test Chamber 17
Notable 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

 * This chamber was actually originally a long level called the "cube run," where players would take the cube through a number of challenges. However, playtesters would leave the cube behind, so they put a heart on it and had the AI keep on talking about it. There is also another Ratman room hidden in this chamber, filled with writing and photographs indicating that Rattmann became obsessed with the cube in some way, and developed a seething hatred for GLaDOS after its destruction.

Test Chamber 18


This is often considered 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.

Trivia

 * At the beginning of the chamber, there is an audio glitch: GLaDOS was supposed to say "You will be baked (bzzzt) cake," as indicated by the subtitles. However, the in-game quote is not censored: "You will be baked, and then there will be cake." This is most likely a development oversight. This quote also foreshadows GLaDOS' betrayal of Chell.

Test Chamber 19
The last chamber. A simple energy ball trick is required, followed by a time-limited sequence on a moving platform.

As the platform rounds a corner, awaiting the player is not the long-awaited cake but a large incinerator. Chell escapes via portals, much to GLaDOS' apparent displeasure; she briefly babbles electronically. She stutters on her "I," revealing her true nature, before regaining control and attempting, unsuccessfully, to convince Chell that this was "the final test, where we pretended we were going to murder you." Chell escapes into the bowels of the Enrichment Center.

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 areas, 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 ASHPD to work her way through the facility.

At first, GLaDOS attempts to calmly dissuade Chell from straying from the test area. But as Chell reaches a series of engine rooms, she falsely claims that the party has started without her. She continues negotiating with Chell, who continues despite the pleading. Finally, GLaDOS starts deploying Turrets and a Rocket Launcher to hinder Chell's progress.

Trivia

 * This section of the game does not bear any official title. "Escape" is the map prefix, and the game files refer to "Behind the Scenes," or "BTS." Within the game itself it's listed as part of Test Chamber 19.


 * The Nice Little Jellyfish is an Easter egg found in this level. It is located in a small office room overlooking Test Chamber 09 that is found soon after the fan blades in the maintenance areas of the facility. It is a faint pencil drawn image on the wall of a smiling jellyfish with the text "nice little jellyfish" under it.


 * The Big Bad Jellyfish is an Easter egg found in this level. It is in a side room on the corridor just before you find the first Rocket Sentry seen in the game. It is a pencil drawing on the wall of an angry looking jellyfish with the text " THE BIG BAD Jellyfish WANTED " under it. Both Jellyfish may have been drawn by Doug Rattmann but there has been no confirmation of this.


 * In the meeting room behind the window adjacent to the "nice little jellyfish" Easter egg, there appears to be a PowerPoint presentation entitled, Competing with BLACK MESA.

Central AI Chamber
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 able to make the call, as the wires were cut.) As Chell destroys critical components of the machine, GLaDOS' 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," possibly the Combine, or something else entirely. After Chell destroys the last component, some form of portal opens above them, tearing apart GLaDOS and sucking in Chell.

Trivia

 * GLaDOS' destruction mirrors the death of the Nihilanth, as they both floated up into an ominous white glow, whilst pulling the protagonist up into the air along with them.


 * It is possible to avoid being sucked up through the portal with GLaDOS by immediately running toward the entrance to her chamber when the turbulence begins, or hiding in the bunker that contains the button to the Incinerator. This, however, does not affect the final cutscene.

Credits
Chell wakes up at the Enrichment Center's gate, among the wreckage of GLaDOS, as debris rains down from the massive, unseen portal. An update designed to build hype for Portal 2 retconned the ending, adding the Party Escort Bot thanking Chell for assuming the party escort submission position and dragging her back inside the facility.

The final cutscene zooms up and through various areas of the Enrichment Center, ending in a darkened room showing 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." It reveals that GLaDOS enjoys the companionship of the test subjects and that it felt a particular fondness for Chell. The song seems to hint that GLaDOS is, indeed, still alive.

When the credits and song end, the player is greeted with a new background: a cake with a lit candle 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

 * Test Chambers 00, 01, 02, 03, 04, 05, 06, 07, 19 and the Relaxation Vault make an appearance in Portal 2, however Test Chamber 06 is modified, Test Chambers 02 and 07 aren't technically "solved" and Test Chamber 19 is navigated backward.