The Winter Soldier is reporting for duty and ready for war.

Captain America franchise star Sebastian Stan recently posted to social media hinting that he is ready to return to the Marvel Universe fold.

Ever since Avengers: Infinity War began production months ago, stars have been dropping hints about their involvement on social media. Michael Rooker even went so far as to trick fans by appearing near their shooting location in Atlanta while donning the Infinity War production beanie, which was recently revealed to be a ruse due to his character’s story in Guardians of the Galaxy Vol. 2. But Stan’s post is a little bit more ominous, with a simple caption of his superhero alter ego’s initials. Stan portrayed Bucky Barnes in all three Captain America films and his involvement in the next big Marvel Studios crossover movie seems inevitable, though production and casting details are being kept secret at this time.

#WS A post shared by Sebastian Stan (@imsebastianstan) on May 18, 2017 at 5:56pm PDT

Stan’s character last appeared in one of the post-credits scenes in Captain America: Civil War, where Barnes goes into stasis in Wakanda until Black Panther and Steve Rogers can figure out away to remove Hydra’s Winter Soldier programming. UP NEXT: Avengers: Infinity War Synopsis Released

As production on Avengers: Infinity War continues, we might learn more by way of set photos taken by fans near the location—the film is currently shooting scenes in Scotland. Some people have already shown pictures and footage of Elizabeth Olsen and Paul Bettany’s characters, Scarlet Witch and Vision respectively, going up against Thanos’ goons. Maybe we’ll catch a glimpse of Stan and his metallic arm sometime soon. Avengers: Infinity War is set to release in theaters May 4, 2018. Are you excited about the latest Avengers movie in the Marvel Cinematic Universe? Let us know with your vote in the Anticipation Rankings below!