The pop star lent her talent to the disembodied voice that played from a helmet back in 2017's Guardians of the Galaxy Vol. 2 but did not return for the 2023 movie; the reason why appears to be unknown.
According to the official press release for Guardians of the Galaxy Vol. 3, Miley Cryus' MCU character Mainframe, who Cyrus voiced in Guardians 2's post-credits in an uncredited role, will now be played by Loki's Tara Strong in Vol. 3.
Tara Strong, a veteran voice actress who has played dozens of popular animated characters like The Fairly OddParents' Timmy Turner and Loki's Miss Minutes, will presumably have at least a somewhat bigger role in Vol. 3 than Cyrus had in Vol. 2, considering the singer's entire role was limited to one line in response to Stallone's Stakar: "I miss you guys so much!"
Mainframe appeared as part of Yondu's team of Ravagers, led by Sylvester Stallone's Stakar Ogord, in the second post-credits sequence of Vol. 2. The star-studded team also featured Michelle Yeoh as Aleta Ogord and Ving Rhames as Charlie-27.
Cyrus' acting career is more closely associated with television than movies thanks to her time as Hannah Montana with Disney Channel, although she did have starring roles in 2009's Hannah Montana: The Movie and 2010's The Last Song, both of which were box office hits.
In the comics, Mainframe — who is male on the page — is an original member of the Guardians of the Galaxy team and was powerful enough to control an entire planet.
Tara Strong Double-Cast In the MCU
With Strong's previous announcement of being in the movie in a non-Miss Minutes role, fans inevitably were left with questions about people playing multiple roles in the vast MCU.
However, this is not only not a first for the MCU, but not the only double-cast in this movie. Linda Cardellini has played Laura Barton — Hawkeye's wife — and is playing Lylla the Otter in Guardians of the Galaxy Vol. 3.
Guardians of the Galaxy Vol. 3 hits theaters on Friday, May 5.