Subsurface Circular is a text-based adventure game lead by designer Mike Bithell of Thomas Was Alone fame. The game follows the story of a robotic detective taking the subway in a city filled with millions of these robots, or “Teks” that serve different jobs for human masters. The main Tek learns that other Teks are going missing, possibly being kidnapped, or worse. Theta, the main Tek, decides to investigate these disappearances, but all while on the subsurface circular (the titular subway system). The player uses dialogue choices and special detective abilities for Theta’s specific android model in order to link together clues gathered from different sources and to solve puzzles. The game’s story also deals with issues and topics of agency, control, truth, and justice, and does all of this using only text-based gameplay with no visible human characters.