The Nomad Soul (known as Omikron: The Nomad Soul in North America) is an adventure game developed by Quantic Dream and published by Eidos Interactive. It was released for Microsoft Windows in 1999 and Dreamcast in 2000. The player can engage in unarmed and armed combat, explore the three-dimensional environment of Omikron City, and talk with non-player characters to progress the story. It follows an investigation into a case of serial killings, which unravels the supernatural truth behind the city's ancient history.

Director David Cage began writing the script in 1994 and signed a publishing deal with Eidos in 1997. David Bowie made the music with Reeves Gabrels, producing ten original songs. The game was finished after two-and-a-half years. Reviewers praised the graphics, soundtrack, story, character models, reincarnation mechanic, voice acting, and combat, but criticised the controls, loading times, and multiple gameplay styles. It was nominated for various awards and sold over 600,000 copies, with low sales in North America. A sequel was planned but cancelled.