The story in Portal 1 is simple, immersive, and in complete service of the gameplay.

Right from the beginning Portal’s world is understandable and engaging. The brief tutorial integrates seamlessly with the story as the player learns game mechanics and explores the recognizable motif of a hi-tech laboratory with a robotic voice coming from the PA. With this uncomplicated setup the story takes off immediately and engages the player.

Keeping with simplicity there’s only two characters (Glados & Chell) and one objective (escape). Glados, for most of the game, exists in the PA system as a sarcastic voice with dubious motives making for a mysterious and entertaining antagonist. The player character is never named in-game but her name is Chell. Her design is the most immersive element of Portal.

Valve’s character design of Chell or more specifically lack of character design is a great creative decision. As mentioned before the player character is never named and only in random glimpses through portals do we even see her. Without a main character identity the game leaves a hole for the player to fill with their own identity. We never learn how Chell feels about the trials she experiences or about her relationship with Glados. The player integrates their own emotions into the game forming a beautiful emotional symbiosis–I’m not pretending to be this character I am this character.

Other immersive elements subtly draw the player’s imagination into the story like hints and clues from environmental storytelling left behind by previous clones of Chell. When Chell dies in the game she’s cloned and brought back so testing can continue. This is a small but really immersive touch because games don’t always address character death and how they return to life.

Radios appear throughout the game all playing the same song that you hear at the very end of the game during the credits sung by the villain, Glados.

So, with a simple, engaging setup and immersive character/game design the effectiveness of Portal’s story can shine in how it completely serves the gameplay. Exposition only shows up through environmental storytelling. With only two characters and no cut scenes it’s through actions with the portal gun and subtly guided exploration that the story unfolds.

Without any other characters the story creates pressure in the form of isolation and hopelessness. No matter how accomplished the player feels after solving a puzzle there’s just another puzzle to be solved. This relentless level design supports the Sisyphean determinism of Portal’s story.

The player is Glados’ test subject and has no choice but to solve each puzzle in hopes of escaping the laboratory. Shooting the portal gun opens up doorways that never lead out of the lab. Rather, every portal you open takes you deeper into Glados’ world, deeper into hopeless isolation.

As the player solves each level the story takes on a sinister tone as Glados’ true motivations are revealed through her dialogue. The player is compelled by the story to push on and solve increasingly challenging puzzles until culminating in the big boss fight where Chell defeats Glados and escapes Aperture Science Laboratories.

Chell reaches the surface at the end of the game and the player has successfully pushed Sisyphus’ boulder to the top of the mountain. However, right before the game goes to credits Chell falls to the ground, still in first person perspective, and we get dragged back into the lab...back down the mountain with the boulder.

Portal’s story and character design create a deep immersive experience because there’s room for the player to emotionally enter the story and the narrative is in complete service of the puzzle solving gameplay and that’s the truest mark of an effective video game story.