Putting aside speculation and hints about supporting characters from the Marvel Cinematic Universe - like Don Cheadle's War Machine - appearing in The Avengers 2, over the last two weeks it's been hinted at and seemingly confirmed that there will be at least two new "heroes" joining Earth's Mightiest for the sequel.
It's the mutant children of X-Men villain Magneto known as Quicksilver and Scarlet Witch. For a variety reasons, they may be quite different from the Marvel Comics version of the characters and the studio may already have an idea of who they want for one of the roles.
SuperHeroHype has the inside info on a few pre-production notes regarding the "brother-sister act" Whedon is excited about writing for The Avengers 2. First and most notably is that the current design of Scarlet Witch is reportedly being based off of young Irish actress Saoirse Ronan, who after hitting the spotlight with an Oscar nomination for her performance in Atonement, has been working consistently on large projects ever since, including City of Ember, Hanna, The Lovely Bones and most recently, The Host.
According to the description of the film's version of Scarlet Witch, known as Wanda Maximoff in the books, Whedon and Marvel will be looking for someone in their twenties to play a British version of the character. Ronan turns 20 next year and is incredibly talented, can do action, and is very familiar with the sci-fi genre.
Wanda, like her twin brother Pietro, is actually of Eastern European decent in the books but fans should expect changes to be made. Not only will her accent and background be altered when it comes to her nationality and family ties, but her origins and powers could be revamped as well. In Marvel Comics, Scarlet Witch and Quicksilver are the offspring of Magneto but due to rights issues those important details cannot be included. This likely means that in The Avengers 2 - if the reports and hints prove true - we're going to see a pair of British super-powered people who are not mutants and have no relation to Magneto.
We expect that their powers will remain the same, but we don't know how they will be explained in the film. Quicksilver has superhuman speed but his sister's ability is much more complex. She can change probabilities and rewrite reality.
Unless by some fanboy miracle Marvel Studios and Twentieth Century Fox are working a deal - much to the happiness of X-Men producer Lauren Shuler Donner and Fox consultant Mark Millar - to have their Marvel film universes crossover or share some semblance of continuity, expect significant changes to be made. Without delving into spoilers, Iron Man 3 took major liberties with key stories from the Iron Man comics and since it represented the first chapter of Phase Two, we shouldn't be surprised if future films do the same.
If Whedon is excited about including these two characters in particular, there will be very important story implications as to why. In the comics, Scarlet Witch rewrote reality, erasing abilities from most mutants on Earth in the major crossover event
House of M. She also has close ties to other key Avengers characters including Wonder Man and Vision - the latter of which was namedropped as a possible theory for how Clark Gregg's Agent Phil Coulson could return from the grave.
Wanda's also shared a unique relationship with the villainous robot Ultron, a creation of original Ant-Man Hank Pym, who of course is getting a debut right after The Avengers 2 in late 2015. Let the speculation run rampant until we know more, but like Marvel President and producer Kevin Feige said, the current first draft of the script could change drastically in six months, much like the Wasp character was dropped from the first team-up in favor of Scarlet Johansson's Black Widow.
Iron Man 3 releases May 3, 2013, Thor: The Dark World on November 8, 2013, Captain America: The Winter Soldier on April 4, 2014, Guardians of the Galaxy on August 1, 2014, The Avengers 2 on May 1, 2015, Ant-Man on November 6, 2015, and Doctor Strange sometime after that.
Let me know on Twitter @rob_keyes what new characters you'd add to the roster of The Avengers 2!