13 Reasons Why actress Katherine Langford has been cast in Avengers 4. Her role is being kept a mystery for the time being. Australian-born Langford is best-known for starring as Hannah Baker in Netflix's 13 Reasons Why, which made its debut in 2017. The actress received a Golden Globe nomination for Best Actress in a Television Series Drama for her performance on the hit series. Langford auditioned for the role of Hannah over Skype and only had a few days to get a work visa since she had never worked in the United States before.

While it has been announced that Katherine Langford will have a part in Avengers 4, it isn't clear who the 22-year old actress will be portraying. According to sources, she has already filmed all of her scenes, which more than likely took place during the recent reshoots, and suggests that she has a smaller role. Reshoots for the highly anticipated film were completed earlier this month, and the Russo Brothers are deep into the post-production process at this time.

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The new Avengers 4 casting adds another mystery for Marvel Cinematic Universe fans to try and solve. All details about the movie, along with the upcoming Captain Marvel and Spider-Man: Far From Home are being kept under wraps, which is the usual deal for Marvel Studios, but Avengers 4 seems to be even more of a mystery than Infinity War and the other movies combined. It's pretty impressive that they were able to keep Katherine Langford's casting a secret for so long, especially in this day and age where set photos leak nearly every day.

It's believed that all of the characters from Infinity War will return in Avengers 4, though it isn't clear how that will be done, or if it will be through flashbacks. We do know that T'Challa and Peter Parker have to come back since they have sequels on the way. The Guardians were supposed to have a sequel, but nobody is even sure if that's happening anymore. Plus, the movie will bring in Captain Marvel, Scott Lang, and Clint Barton, who were not around during the events of Infinity War to help take down Thanos.

Marvel Studios boss Kevin Feige just revealed that the trailer for Avengers 4 will officially come out by the end of the year, which means that we're only a few months away from seeing the first sneak peek at the sequel. This one is for all of the marbles, and it doesn't seem like everybody will be making it out alive this time around, especially considering Elizabeth Olsen stated the movie will be darker than Infinity War. In addition, it's believed that the film will be Chris Evans' last time as Captain America and Robert Downey Jr.'s last time as Iron Man. The Katherine Langford Avengers 4 casting information was first announced by The Wrap.