Supergirl has her hands full in present-day Metropolis, battling enhanced Terminators that anticipate her every move. If she can't stop the wave of destruction, Metropolis will be reduced to an urban junkyard. Meanwhile, transported to the future, Superman is reunited with his old friend Steel to face Sky-1, the Skynet robot. With Skynet and the Cyborg forming a seemingly invincible alliance, only one person can stop them: a boy named John Connor.