It is a squeal to Captain America (2009). He is now a highly skilled fighter and a top S.H.I.E.L.D. It turns out the most of S.H.I.E.L.D is Hydra. Bucky Barnes has come back as The Winter Soldier. Cap, Falcon, Hawkeye and Black Widow have to stop him to turn him back. Nick Fury has his own action scene. This is Part of the Marvel Cinematic Universe (MHM15).