Superman rescues Dr. Leo Quintum and his
P.R.O.J.E.C.T. team from an exploration mission to the
Sun that was remotely sabotaged by
Lex Luthor, and acquires the ability to project his bio-electric aura. Luthor orchestrated this event to overwhelm Superman's cells with massive amounts of solar radiation, which greatly increases his power but is also killing him, with Quintum giving him one year left to live. Luthor is arrested after the publication of a
Daily Planet article written by
Clark Kent, while Superman decides to keep his impending death secret from the public. Nonetheless, Superman reveals his secret identity to
Lois Lane to spend his remaining time with her. Although Lois initially refuses to believe this, Superman treats her to a birthday dinner in the
Fortress of Solitude. Superman's furtive behavior and an airborne chemical in the raised and restored
Titanic rouses paranoia in Lois and she accidentally attacks Superman with a
Kryptonite laser, but he is unharmed by it due to his new powers. Superman calms her down and reveals that he had been preparing her birthday present: a liquefied form of his DNA that will grant her all his superpowers for 24 hours, as well as a leotard costume. Using the name "
Superwoman", she joins Superman as he stops a monster attack in
Metropolis involving Samson,
Atlas and an Ultra-Sphinx. Superman drives Samson and Atlas away and he and Lois spend an eventful day that ends with them kissing on the moon before her powers fade and she falls asleep. Superman flies her back home. Meanwhile, Luthor is convicted of crimes against humanity and sentenced to death. Clark meets with Luthor for an interview at
Stryker's Island. Following a violent encounter with the
Parasite in which Clark manages to conceal his identity, Luthor reveals that he respects Clark as a journalist and that he has no desire to escape because he has fulfilled his dream of killing Superman. Nearing death, Superman accomplishes the "Twelve Labors of Superman" – a variety of tasks that significantly help both humans and
Kryptonians – and completes his last will and testament. Meanwhile, Luthor survives and escapes his execution after taking a formula similar to what Superman made for Lois, and he begins razing Metropolis with the aid of
Solaris, an artificial star that corrupts the Sun and turns it red. After Superman defeats Solaris, Clark returns to the
Daily Planet to submit his article, but falls dead. As the staff tries to save him, Superman awakes on his home planet of
Krypton and meets his father
Jor-El, who reveals that Superman's body is converting itself to a solar radio-consciousness. He offers him a choice; remain dead or return to life long enough to defeat Luthor. Clark wakes up, and confronts Luthor, firing a gravity gun at him. The gravity gun warps time for Luthor, speeding up the exhaustion of his powers. As his powers fade, Luthor briefly sees Superman's vision of Earth, and weeps before Superman knocks him out. Superman proclaims his eternal love for Lois and kisses her before becoming a solar consciousness and repairing the Sun. One year later, Lois admires a monument dedicated to Superman and tells
Jimmy Olsen that she believes Superman will return if he can create an artificial heart for the Sun. Superman, now a solar being, lives inside the Sun and maintains machinery to keep it alive. Meanwhile, Quintum reveals a new P.R.O.J.E.C.T in case something happens, and unveils it by standing before a door with Superman's characteristic emblem, with its usual "S" replaced with the number "2". ==Reception==