The Universal Soldier series primarily stars Jean-Claude Van Damme and Dolph Lundgren, who have appeared in all the official entries. Van Damme plays Luc Deveraux, a soldier killed in the Vietnam War and reanimated in the 1990s as a highly advanced super-soldier. Lundgren plays Andrew Scott, also a Vietnam soldier, who suffers a psychotic break before being reanimated and is Deveraux's nemesis for the majority of the series.
After The Return was met with overwhelming critical and financial failure, the subsequent film in the series, Universal Soldier: Regeneration, ignored and often contradicted the events of that film. The Return is no longer considered part of the series canon. Universal Soldier: Day of Reckoning featured Van Damme and Lundgren in much smaller roles, featuring a new protagonist named John (Scott Adkins) fighting against both Deveraux and Scott.
John Hyams, director of Regeneration and Day of Reckoning, has said there may be more films to come, but until they get feedback on the fourth installment they would not yet go ahead with a fifth.