On an uninhabitable 22nd-century Earth, the outcome of a civil war hinges on cloning the brain of an elite soldier to create a robot mercenary.
Kara, devastated by the loss of Krypton, struggles to adjust to her new life on Earth. Superman mentors her. Meanwhile, she must contend with a mysterious group called the Dark Circle who searches for a powerful weapon held in the Academy's vault.
Humans built huge engines on the surface of the earth to find a new home. But the road to the universe is perilous. In order to save earth, young people once again have to step forward to start a race against time for life and death.