The Oscar winner starred in 2014's blockbuster Kingsman: The Secret Service, but his secret agent character Harry Hart was killed at the end of the film - or so it seemed.
Ever since Kingsman: The Golden Circle started coming together earlier this year (16), rumours about Firth's return were rampant, with some film insiders suggesting he would be portraying his deceased character's twin.
And now, in a snap shared by new cast member Pascal, it appears the actor has at least been visiting the set.
The Game of Thrones star took to Instagram on Sunday (10Jul16) to share a selfie of himself alongside Firth in Harry's signature glasses, adding the caption, "Hide behind Harry. #SafePlace #Kingsman2 #TheGoldenCircle."
While it is still unclear what Firth's role in the new film will be, his return isn't entirely unexpected. The behind-the-scenes photo comes after director Matthew Vaughn hinted he might try to revive the character, while a promotional poster released in April (16) featured Harry's spectacles and the line, "Reports of my death have been greatly exaggerated."
Taron Egerton and Mark Strong will return for the sequel, while Julianne Moore, Halle Berry, Channing Tatum, and Jeff Bridges are all set for roles, and Sir Elton John has a cameo.
Kingsman: The Golden Circle is scheduled to hit cinemas in June, 2017.
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