Three years after the events of the Species (film), Commander Patrick Ross leads a Human mission to Mars to Mars. Soil samples collected by Patrick's team of astronauts unwittingly contain an extraterrestrial substance which thaws aboard their capsule due to the temperature difference and contaminates them, causing a seven-minute contact gap with mission control. With seemingly no subsequent negative effects, the astronauts return to Earth to public celebration. Only an institutionalized former scientist, Dr. Cromwell, reacts to their return with violent panic. Meanwhile, Dr. Laura Baker has created a clone of Sil named Eve, whose alien DNA is suppressed to make her more docile. Her team conducts experiments on Eve, hoping to find a way to combat the alien species should it ever return to Earth. Every experiment is unsuccessful as Eve's biology adapts.