The DC Universe (DCU), under the stewardship of James Gunn and Peter Safran, is poised for a bold new era, with Superman soaring to a $200-million opening weekend on July 11, 2025, and Supergirl: Woman of Tomorrow set for June 2026. Yet, amidst the buzz surrounding David Corenswet’s Man of Steel and Milly Alcock’s Kara Zor-El, fans on X are rallying behind a singular, audacious idea to propel DC past its rival Marvel: cast Sydney Sweeney as Power Girl, the Earth-2 counterpart to Supergirl. The sentiment, epitomized by posts like “just put Sydney Sweeney in the Power Girl outfit,” reflects a belief that her star power and the character’s bold persona could ignite a box-office inferno, outshining Marvel’s recent struggles post-Avengers: Endgame.

Sweeney, fresh off roles in Anyone But You and Immaculate, has emerged as a fan-favorite for superhero roles despite the critical flop of Madame Web, where she played Spider-Woman Julia Carpenter. Fan art by Davi Alves, shared widely on X, depicts Sweeney in Power Girl’s iconic costume—complete with its signature windowed design—flexing her charisma and physicality. Posts on X, like one from @thelegacyofnerd claiming Sweeney as Power Girl would “break every box office record,” underscore the fervor. Fans see her as a perfect fit for Karen Starr, Power Girl’s alter ego, whose confidence, strength, and distinct identity set her apart from Supergirl’s more reserved heroism.

Power Girl, created by Gerry Conway and Ric Estrada in 1976’s All-Star Comics #58, is a Kryptonian from Earth-2 with powers mirroring Superman’s but a personality that’s fiercely independent. Unlike Kara Zor-El, who arrived on Earth as a teenager, Power Girl’s maturity and unapologetic attitude resonate with Sweeney’s ability to blend vulnerability with commanding presence, as seen in Euphoria. Fans argue that her casting would not only capitalize on her rising star—bolstered by 2025’s Echo Park alongside Julianne Moore—but also offer a fresh, dynamic female lead to rival Marvel’s inconsistent post-Endgame slate, where projects like The Marvels underperformed.

James Gunn’s DCU, launched with Creature Commandos in 2024 and anchored by Superman’s critical acclaim, emphasizes tonal diversity, from the cosmic fantasy of Supergirl to the gritty Lanterns. Introducing Power Girl could amplify this vision, bringing a character who’s both a powerhouse and a symbol of self-assured femininity. Fans on X, like @sandeeprathi100, call her casting “box office gold,” envisioning memes and global hype that could eclipse Marvel’s formulaic team-ups. Sweeney’s ability to navigate complex roles, as evidenced in Immaculate’s strong reviews, suggests she could embody Power Girl’s blend of strength and moral ambiguity, distinct from Alcock’s “messy” Supergirl, described by Gunn as a traumatized, impulsive heroine.

The DCU’s reboot has sparked debate, with some fans wary of Gunn’s comedic leanings from Guardians of the Galaxy and The Suicide Squad. Critics on Reddit’s r/DCcomics question whether his approach risks turning characters like Power Girl into comic relief, citing his portrayal of Supergirl’s irreverent cameo in Superman. Yet, supporters argue Gunn’s knack for humanizing heroes, seen in Rocket Raccoon’s emotional depth, could elevate Power Girl beyond her comic book “boob window” stereotype into a nuanced figure. Sweeney’s candid response to Madame Web’s failure—“I was just along for the ride”—shows her resilience, making her a compelling choice for a character who owns her narrative.

Marvel’s recent stumbles, with mixed reception to Thunderbolts and Captain America: Brave New World, have left an opening for DC to seize the superhero crown. A Power Girl film or series, with Sweeney’s star power, could mirror Wonder Woman’s 2017 cultural impact, especially if paired with Alcock’s Supergirl in a multiverse storyline. Fans on r/Fancast note Sweeney’s youth might contrast with Power Girl’s mature persona, but her proven range could bridge the gap, offering a fresh take on a hero who’s never led a live-action project.

As Gunn teases Justice League plans and Wonder Woman’s return, the clamor for Sweeney as Power Girl grows louder. Whether DC Studios heeds the call remains uncertain—no official plans for the character exist—but the fan-driven momentum suggests a cultural moment waiting to happen. If Gunn listens, Sweeney’s Power Girl could redefine DC’s edge, proving that sometimes, a costume and a star are all it takes to steal the spotlight.