Samuel L Jackson, Cobie Smulders and Scarlett Johansson are all to reprise their Avengers roles in Captain America: Winter's Bone.
The trio, who appeared as SHIELD team Nick Fury, Maria Hill and Black Widow in Marvel comic film Avengers Assemble, have all joined the adventure sequel, Variety reported.
It has also been confirmed that Frank Grillo will play villain Crossbones in the film.
The Prison Break star tweeted last week that he had done a screen test for a role in the Captain America sequel, and hinted which character with the hashtag "bones".
The character first appeared in the comic series in 1989 as Brock Rumlow, a leader of the New York Savage Crims gang before joining a school for criminals and becoming a henchman of the Red Skull under the code name Crossbones.
Chris Evans returns as the comic book superhero in the eagerly awaited follow-up, along with Sebastian Stan as Bucky Barnes, who becomes assassin the Winter Soldier.
The role of the Captain's love interest is still being cast, with Downton Abbey star Jessica Brown Findlay apparently battling it out for the part against Imogen Poots, Teresa Palmer, Community actress Alison Brie and Game Of Thrones' Emilia Clarke.
Anthony Mackie, who has starred in The Hurt Locker and Abraham Lincoln: Vampire Hunter, is also on board as new character The Falcon.
Anthony Russo and Joe Russo are directing the film from a script by Christopher Markus and Stephen McFeely, with the release date already set for April 4, 2014.