Marvel adds Disney child star to Avengers: Doomsday cast

Robert Marvel Studios has confirmed that English actress Matilda Firth, known for Disney’s Disenchanted, is part of the upcoming Avengers: Doomsday ensemble, listed under the vague character name “Little Girl” [2]. The film, directed by the Russo brothers and slated for a December 18, 2026 release, already boasts a sprawling cast that spans the Avengers, Fantastic Four and X‑Men universes [1].

Key takeaways

• Matilda Firth, who debuted as Bella in Disney’s Disenchanted, is credited as “Little Girl” in Avengers: Doomsday [2].
• The role is currently undefined, leaving open the possibility of a brief cameo or a hidden major character [2].
• Avengers: Doomsday will feature an unprecedented crossover of heroes from multiple universes, with filming completed in September 2025 [1].
• The film is scheduled for release on December 18, 2026, marking the first Avengers theatrical outing since 2019 [1].

Expanding the MCU’s biggest ensemble

Avengers: Doomsday brings together characters from the classic Avengers roster, the new Fantastic Four, and the original X‑Men, all converging to confront Robert Downey Jr.’s Doctor Doom [1]. The Russo brothers returned to direct, with Michael Waldron and Stephen McFeely handling the screenplay, and principal photography wrapped at Pinewood Studios in England in September 2025 [1]. Among the confirmed veterans are Chris Hemsworth’s Thor, Anthony Mackie’s Captain America, and Ian McKellen’s Magneto [1].

The addition of Matilda Firth, whose agency lists her under the generic “Little Girl” credit, adds a youthful element to a film already packed with marquee names [2]. Her previous work includes a feature debut in Disenchanted, a horror reboot Wolf Man, and a thriller Subservience, as well as TV roles on ITV’s Mr Bates vs The Post Office and Hulu’s Nine Perfect Strangers [2]. The lack of detail on the agency page means the size of her part remains uncertain, prompting speculation about whether she will appear only briefly as a background civilian or serve as a cover for a more significant, surprise character [2].

Why it matters

Marvel’s practice of masking key roles behind vague credits suggests that Firth’s “Little Girl” could be a strategic tease, keeping fans guessing until the film’s release [2]. If the role proves larger than a cameo, it would underscore the studio’s willingness to integrate newer talent alongside established stars, enriching the narrative complexity of a multiverse‑spanning showdown. The film’s December 2026 debut will be the MCU’s first major Avengers installment in seven years, and the inclusion of a Disney child star highlights Marvel’s continued cross‑brand collaboration within Disney’s broader entertainment ecosystem [1][2].