Captain America: The Winter Soldier (2014)

Widely regarded as the best flick of Marvel Cinematic Universe’s Phase II, Captain America: The Winter Soldier showed everybody that HYDRA was far for being dead. It is revealed that Senator Stern is one of its agents and that even SHIELD was compromised at all its levels.

Furthermore, the movie also brings back a figure from Steve Rogers’ past, in the form of the Winter Soldier – captured by HYDRA during the events of Captain America: The First Avenger, Bucky Barnes has been brainwashed and transform into an assassin. Sent after Nick Fury, he clashes with Steve Rogers, without recognizing him.

Captain America: The Winter Soldier also introduces the Falcon, as one of the future Avengers. The mid-credits scene leads directly into Avengers: Age of Ultron – baron von Strucker has found the Scepter of Loki and used it to create new superpowered beings, namely Quicksilver and Scarlet Witch.