Geraldine Viswanathan has carved out a Hollywood career most Australian actors only dream of. From stand-up gigs at the University of Sydney to indie comedy troupes, her rise has been unconventional and impressive. The breakout moment came when she landed a starring role in Blockers alongside John Cena, turning what could have been just another audition into a gateway to the big leagues.
“I was two weeks into training as a Triple J host when I got the call,” Viswanathan told ABC Entertainment. “I emailed them like, ‘I have to go do this film with John Cena. Love you!’”
Fast forward to 2025, and the 29-year-old actor is officially part of the Marvel Cinematic Universe. She joins Thunderbolts*, Marvel’s final Phase Five film — a high-stakes project coming at a time when the studio desperately needed a win. The film has turned out to be a critical and commercial success, earning $162 million in its opening weekend and offering fans what many describe as “the best Marvel movie in years.” 
Originally stepping in for Ayo Edebiri due to scheduling conflicts, Viswanathan took on the role of Mel, the razor-sharp assistant to Julia Louis-Dreyfus’ Valentina Fontaine. “Mel isn’t a superhero, but she’s powerful in a different way,” she says. “It’s cool to play someone ambitious, who begins to question whether she’s on the right side.”
While the Thunderbolts are a motley crew of antiheroes, Mel emerges as the emotional and ethical center — a complex character navigating power dynamics, loyalty, and morality in a universe not known for subtlety. “This is the kind of layered, female-driven dynamic I’ve always wanted to be part of,” Viswanathan shares.
The moment she first stepped on set was unforgettable. “There were helicopters, hundreds of extras, trucks… and I just thought, ‘If I mess this up, all of this has to reset.’ It felt like live theatre with Marvel-sized stakes.”
As for what she’d say to her younger self grinding it out on tiny sets and open mic nights?
“Keep going. Don’t stress — it’s all going to be fine,” she says, laughing. “Also, maybe rethink the extremely high-waisted pants.”
