Star Trek Alien Domain is a free-to-play sci-fi strategy game played in a web browser. The game features a unique Star Trek story, and dozens of new starships and alien species. Players join one of two factions (Klingon or Federation) and journey through fluidic space to build the strongest fleet, and defeat their enemies.

The game takes place in the Star Trek timeline after the TV series, Star Trek: Voyager. The game begins with players investigating a new anomaly, only to find themselves sucked through a quantum fissure and arriving in Fluidic Space, one of the most unexplored areas of the Star Trek universe.

The dominant species in Fluidic Space, Species 8472, has decided to go against its recent treaty with our universe, and has begun slowly capturing Federation and Klingon forces (and others yet to be seen) in order to weaken their power, and study them further. Players must band together to survive the new threats posed by both Species 8472, and by other players.