Action/adventure series based on the Marvel Comics title "Mutant X." The public is unaware of the existence of genetically altered people -- mutant offshoots of medical experiments meant to create "designer babies," or of the covert agency called the Genetic Security Agency (GSA) that is hunting them down. The Mutant X's main four -- Brennan, who can conduct electricity; Emma, a telepath who can influence other's behavior, Shalimar, whose DNA is half-human animal; and Jessie, who can alter his body density -- live and work in a sanctuary run by their leader Adam Xero. The third season begins with Emma dead from an explosion, Adam lost and presumed dead and the addition of the mysterious Lexa Pierce.