Celia Massingham is an Australian actress whose career encompasses live-action television and film, with a recent foray into high-profile voice acting for an animated series. Her body of work, while not extensive in volume, demonstrates a versatility that spans period drama, superhero television, and cutting-edge animation production.

Massingham's early career includes roles in Australian film productions. She appeared in the 2012 comedy Reef 'n' Beef and the 2013 film Greg's First Day. In 2018, she had a role in the acclaimed Australian comedy-drama Ladies in Black, which is adapted from the bestselling novel by Madeleine St John. Her television work during this period included a guest appearance in the first season of the popular CW superhero series DC's Legends of Tomorrow, where she portrayed the famous Hollywood actress and inventor Hedy Lamarr.

Massingham's most significant and high-profile role to date came in 2024 with the Netflix original anime series Mobile Suit Gundam: Requiem for Vengeance. She was cast as the lead character, Captain Iria Solari, a Zaku II pilot and the commander of the Red Wolf Squadron fighting for the Principality of Zeon on the European front during the One Year War. This role was notable not only for being her first major voice acting credit in animation but also for its technical demands. In addition to voicing the character in English, Massingham also performed the motion capture for Iria Solari, providing the physical performance that was translated into the character's CGI animation. This dual role was central to the production, which was groundbreaking for being the first in the Gundam franchise to be made entirely with Epic Games' Unreal Engine 5.

The series, a six-episode collaboration between Bandai Namco Filmworks and SAFEHOUSE, was created with a global audience in mind, and Massingham's performance as the lead was a key component of its international release on Netflix. Her casting in such a technically advanced and narratively significant role within a legendary franchise marks a major achievement in her career, establishing her presence in the world of anime and video game-style animation production.