Photopia is a piece of literature by Adam Cadre rendered in the form of interactive fiction, and written in Inform. It is regarded as a pioneer in narrative-driven, rather than puzzle- or challenge-driven, interactive fiction, and is perhaps the most successful example of this genre to date. It won first place in the 1998 Interactive Fiction Competition.
Photopia has few puzzles and a linear structure, allowing the player no way to alter the eventual conclusion but maintaining the illusion of non-linearity. This gives weight to some of the story's motifs -- questions of free will and determinism.
He submitted Photopia to the 1998 Interactive Fiction Competition pseudonymously. He felt that his previous game I-0 would inspire certain expectations in players, since in that game the player character is a young college student who could be instructed to undress. Years later, he dropped the pretense that "Opal O'Donnell" had written Photopia: "it started to bother me that v1.0 of the Phaq had lies in it."