Quicksilver

"It's not a world of spies anymore, not even a world of heroes. This is the age of miracles, doctor. There is nothing more horrifying than a miracle!"

- Baron Strucker Quicksilver is a character in the Marvel Cinematic Universe set to appear in Avengers: Age of Ultron and is the twin brother of Scarlet Witch. He will be portrayed by Aaron Taylor-Johnson.

Captain America: The Winter Soldier
Quicksilver and Scarlet Witch appear in a mid-credits scene with Baron Strucker, which confirmed that they were not present at SHIELD's headquarters at the time HYDRA was defeated there and Operation Insight was shut down due to Baron Strucker's actions. Strucker also revealed he intended to use them for an unspecified purpose.

Avengers: Age of Ultron
In May 2013, Entertainment Weekly  reported that Quicksilver and his sister, the  Scarlet Witch, would appear in the 2015 film  Avengers: Age of Ultron , which was later confirmed by director  Joss Whedon. In October 2013,  Aaron Taylor-Johnson  was cast in the role of Quicksilver.

The Avengers: Earth's Mightiest Heroes
Pietro along with his father and sister, went to Avengers Mansion, to claim the Wasp for the Brotherhood of Mutants, believing that she is a mutant, due to a rumor in the news. Facing the Avengers, Captain America throws his shield directly to Magneto, but Pietro manages to catch it with ease, before it hits his father in the head.

When the Wasp claimed that she not is mutant, Magneto is beaten by a brick thrown by one anti-mutant protestors were in the mansion, what does infuriated him, changing their target of attack towards other humans.

This makes Pietro and his sister be made against his father, who imprisons them with pieces of metal, being released by the Wasp, who along the Avengers, attack to Magneto, demanding to his father for his attitude, forcing him to escape from the pclice, claiming that they will be on his side in the war, or be destroyed.

After the attack, Iron Man tells Wanda and Pietro to come with them, and Jan explains that she is not a mutant, but the Avengers  don't mind it if they are, and also speaking to the crowd that regardless of whether they are, they fight against the bad guys together, Quicksilver grabs the Scarlet Witch and escape, but not without telling the Avengers that they have given the siblings something to think about.

Trivia

 * Another version of Quicksilver appears in the 2014 superhero film X-Men: Days of Future Past. Since the film is owned by 20th Century Fox, the Quicksilver in that film is a completely seperate adaptation of the character from the one featured in this article nor is he part of the Marvel Cinematic Universe.