Firefly star Nathan Fillion has boarded James Gunn's The Suicide Squad.

According to Deadline, Fillion has joined The Suicide Squad, though his role in the film is not known at this time. Fillion previously worked on Guardians of the Galaxy with Gunn, playing an inmate during the movie's prison scenes. He also appeared in posters as Simon Williams/Wonder Man for the 2017 sequel, though they didn't make the final cut.

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Gunn will be directing both Guardians of the Galaxy 3 and The Suicide Squad. In addition to Fillion, the movie will also reportedly feature the additions of Idris Elba and John Cena. Comedian Steve Agee is also said to be voicing King Shark in the upcoming film. Benicio Del Toro is rumored as playing the film's villain.

Written and directed by James Gunn, The Suicide Squad is set to hit theaters on Aug. 6, 2021. Several cast members from 2016's Suicide Squad will reprise their roles, including Margot Robbie as Harley Quinn, Viola Davis as Amanda Waller, Joel Kinnaman as Rick Flagg and Jai Courtney as Captain Boomerang.

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