Next we follow-up with Captain America and his adventures in the Winter Soldier. Here we are introduced to Sam Wilson aka Falcon, who becomes an integral part of the Avengers. 

This film touches upon rich and deep Marvel lore as it focuses on S.H.I.E.L.D.’s and Captain America’s foremost and prominent foe- Hydra. Contrary to what some may think, Red Skull is not the originator of Hydra but is responsible for making it into the incarnation it became in World War II as well as naming it Hydra as it was nameless prior and was merely a cult that existed for thousands of years. The Red Skull’s legacy lives on to this day. 

The Winter Soldier is a complex espionage, conspiracy, and spy film that is cleverly laid out and it may be difficult to keep up with the more intricate details of the plot. It serves the MCU by bringing Bucky back as the Winter Soldier and the fact that Hydra had been operating under S.H.I.E.L.D’s very nose for many years thus making those connections to the previous Captain America film and further expanding and developing his story and character. 

The core plot of the Winter Soldier sees S.H.I.E.L.D dealing with an operation known as Project Insight in which three Helicarriers target and exterminate potential threats to S.H.I.E.L.D. The leader of the operation is Alexander Pierce, the man who gave Nick Fury his place within S.H.I.E.LD. When Nick Fury attempts to infiltrate a S.H.I.E.L.D vessel by way of hiring mercenaries to ambush it conspicuously to give him a reason to send in his counter-terrorism S.T.R.I.K.E team, he secretly deploys Black Widow to retrieve information concerning Project Insight. When he tries to decipher it and can’t, he becomes suspicious and tells Pierce to delay the Project. This, in turn, causes the Winter Soldier to be deployed and to assassinate Fury since he has become a liability to the Project. 

In the First Avenger, Bucky had fallen off the train carrying Arnim Zola on it (Red Skull’s primary scientist who assisted Red Skull in being able to use the Tesseract’s power) and was presumed dead. Hydra had found Bucky, revitalized him using a variant of the Super-Soldier serum, and rewired his brain to forget his former identity and work for Hydra. 

Fury, shortly before being dispatched by Bucky, tells Rogers to not trust anyone. When Rogers is questioned by Pierce and informs Rogers that he received intel that Fury spoke to Rogers, Rogers doesn’t disclose what Fury told him thus becoming a fugitive and going on the run with Black Widow. Using the data in the hard drive that Natasha extracted from the vessel, they go to the coordinates that the data contains and discover a hidden bunker in New Jersey where the consciousness of Arnim Zola had been preserved and here he reveals that Hydra had all along been working within S.H.I.E.L.D. With the help of Sam Wilson, they deduce that an agent named Jasper Sitwell knows about Project Insight and from him they discover that Zola figured an algorithm to target potential threats to Hydra with one of them being Stephen Strange. During all this Captain America discovers that the Winter Soldier is his best friend Bucky which serves as a great secondary plotline. 

At the end of the day, our heroes stop Project Insight, Nick Fury is still alive, Bucky and Cap clash twice concluding with Bucky saving Steve’s life, and at the end credits, we see Bucky at a Smithsonian museum reading up on himself about his ventures during World War II indicating that he is remembering who he truly is. 

Notable Captain America villains which appear are Brock Rumlow, leader of the Counter-Terrorism Strike Force aka Crossbones and Georges Batroc who Captain America fights at the beginning of the film aka Batroc the Leaper.

EDIT: HYDRA’S THOUSAND-YEAR HISTORY IS NO LONGER CANON AS IT SEEMS THAT THE DISNEY PLUS SHOWS CONTRADICT WHAT OCCURS IN ANY MARVEL LEGACY SERIES (see Marvel TV Shows Guide List)