Weeks after Lex Luthor’s arrest, the impeachment of his presidency, and Batman’s successful save of the world from a looming meteor threat, a spaceship lands in Gotham Harbor and a young girl steps out, unable to speak any human language. The girl’s Kryptonian-like powers unleash havoc until the Dark Knight, Kevin Conroy, exposes her to a fragment of Kryptonite. With the help of Tim Daly as Superman, they gradually learn that this newcomer is Kara Zor-El, Summer Glau, the niece of Jor‑El and Superman’s biological cousin. The moment is both awe-inspiring and unsettling, as Kara’s arrival upends the fragile balance of trust and caution that already hovers over Earth’s protectors.
Kara is welcomed by Superman, who greets her with warmth and patience. He helps her learn English and begins guiding her as she adjusts to life on Earth, while Batman remains suspicious of the girl’s sudden appearance and extraordinary powers. The tension between hope and doubt threads through their interactions, even as Kara shows a genuine desire to understand this new world and its people.
Tipped off by Batman, Wonder Woman and Lyla / Harbinger / Artemis ambush Clark Kent and Kara in a park, and they whisk Kara away to Themyscira so she can learn to control her powers in a safer, more supervised setting. The Amazonians’ island is a stark contrast to Gotham’s grit, a place of fierce training and ancient discipline, where Kara begins to be guided by warriors and sages who have faced threats far older than her.
Back on Earth, the threat shifts toward Apokolips. On that distant, fire-scarred planet, Darkseid learns of Kara’s presence on Earth and orders her capture, hoping to recruit or coerce her into leading the Female Furies in the wake of Big Barda’s departure. The stakes rise as the cosmic tyrant’s interest in Kara becomes personal, and the heroes realize that the fate of two worlds hangs in the balance. As Batman and Superman keep watch over Kara’s welfare from Themyscira, a monstrous influx arrives in the form of Doomsday clones flooding toward Earth, spurred by Apokolips’s dark forces. The Amazonian army stands firm, but the sheer scale of the threat presses Kara into a crucible that tests every ounce of her strength.
In a brutal clash, Superman unleashes a devastating heat-vision assault that vaporizes the Doomsday clones, but the victory is shadowed by a grim twist: Kara disappears from sight, and Lyla is killed by Darkseid’s Omega Beams as a grim reminder of what is at stake. Distraught, Superman vows to rescue Kara and to avenge Lyla, a mission that will drive the alliance of heroes to the edge of endurance. Batman, Superman, and Wonder Woman—joined by Barda for Earth’s sake—recruit Big Barda Julianne Grossman to help them navigate Apokolips’s perilous terrain and to marshal the aid of every ally who can stand against Darkseid’s might.
The team journeys into the fire-lit world of Apokolips. A relentless battle unfolds in the palace and through the planet’s sewers, where Granny Goodness and the Female Furies press hard against the intruders. Batman moves underground and uncovers the Hell Spores—the fiery core that fuels Apokolips’s brutal arenas and battles—and activates them, turning the landscape into a deadly trap for Darkseid’s forces. The confrontation with the tyrant intensifies as Darkseid uses Kara, now brainwashed, to attack Superman. Batman steps forward with a stark ultimatum: if Darkseid frees Kara and agrees to leave her alone and allow the Hell Spores to be deactivated, then Darkseid may walk away with his Earthbound prize left intact.
Darkseid, drawn to Batman’s cunning, concedes in a rare moment of respect, admitting admiration for the Caped Crusader’s tactics. The result is a fragile truce of sorts: Darkseid withdraws, and the heroes with the subdued Granny Goodness in hand depart Apokolips, leaving the tyrant to brood on his next move. Back on Themyscira, Kara contemplates the fear that dark impulses might lurk within her, wondering if Darkseid merely sought to manipulate an inner darkness to bend her to his will. Superman reassures her that Darkseid represents an evil that exists outside of her, and that Kara possesses the strength of character to choose what she becomes.
With life gradually returning to normal, Clark takes Kara to meet his adoptive parents in Smallville, hoping she can settle into a true sense of belonging. But Darkseid has not finished with Earth; he ambushes them, breaking his promise to spare Kara and turning his attention to Superman. Omega Beams blast Superman into orbit, forcing Kara to stand alone against the tyrant. A fierce and lengthy duel ensues—Kara, now tempered by both Amazonian and Apokoliptian training, holds her own but cannot crush Darkseid on her own. Superman returns just in time, trading blows with Darkseid at super speed and fending off Darkseid’s Omega Beams, while Kara uses Darkseid’s Mother Box to activate a Boom Tube behind the tyrant. The distraction lets Superman push Darkseid through the portal, sending him to a distant point in space where he becomes trapped, frozen in ice as a cosmicwarning.
Having saved her cousin and found her place on Earth, Kara embraces a purpose greater than survival: to fight for altruism as Supergirl. Her theophany of resolve earns a warm, public welcome from Wonder Woman, the Amazons, and Batman, who all acknowledge her new role as a guardian of Earth. The team’s arduous journey ends with Kara and Superman soaring toward Metropolis, where a future of hope and heroism awaits, and the path of a new protector — Supergirl — begins in earnest.
