The game takes place in an alternate reality from the series and features a cast of new characters, however it shares similar themes to the anime.
Serial Experiments Lain was released shortly after the conclusion of the anime and developed concurrently. Calling it a "game" may be a bit of a stretch, and the creators actually define it as "psychostretchware". Instead of actual gameplay, it acts more as an interface to access parts of Lain's story, presenting a multimedia experience that includes video, diary excerpts, and notes from Lain's therapist. Although it has yet to receive an English version, officially or unofficially, some fans have translated it and put it into a PDF format, available to download.
This game contains examples of:
- Adaptation Dye-Job: Lain's dark brown hair has a heavy purple tint. It's probably Purple Is the New Black.
- Alternate Universe: The game takes place in a separate continuity from the anime and features a completely different plot.
- Ambiguous Disorder: It's even more pronounced due to Lain's Creepy Child factor being ramped up. Lain's therapist lists her as having multiple mental disorders.
- Bloodier and Gorier: The anime is relatively tame on its gore. This game? Not so much. It has a lot of blood and dead bodies. Lain slashes her throat, kills her therapist, beats up her dad's half-finished android, and ultimately shoots herself.
- Darker and Edgier: It's more grim and graphic than the anime.
- Driven to Suicide: Lain shoots herself in the end. Played with in that she possibly only killed her physical body.
- The Hero Dies: Lain dies by shooting herself.
- Replacement Goldfish: After Lain's parents divorce, Lain creates an AI replica of her father. She later tries to make a physical android in which to place the AI.
- Self-Harm: At one point Lain smashes a mirror and sinks a piece of glass into her neck.