GWW (the same site that recently broke the news about World War Hulk being on the way) is claiming that Thunderbolts is set to begin production in 2023. It will reportedly be a movie, though it won't be the only big screen project that work begins on that year; Fantastic Four and Nova are also mentioned, while that Okoye series and a Shang-Chi spinoff are also slated for the year after next.
The site doesn't have any plot details, but it's been obvious for a while now that Marvel Studios appears to be building to a team of villains and anti-heroes assembling in place of The Avengers.
Valentina Allegra de Fontaine is up to something, and we've already seen her recruit John Walker as her U.S. Agent along with Yelena Belova (who she's sent in Hawkeye's direction). Clearly, she has ambitious plans for these characters, and this Government-backed "Avengers" would likely make General "Thunderbolt" Ross very happy indeed.
He could even be involved (the name is kind of a giveaway), and Thunderbolts beginning production in 2023 means that Marvel Studios has a while longer to continue using Val the same way they once did Nick Fury. We're not sure what this is building to, but Kevin Feige is said to be interested in a Dark Avengers project of some sort.
In the comic books, the Thunderbolts have been portrayed as a team of villains led by Baron Zemo who posed as heroes for their own means. They've also been used in a similar way to DC's Task Force X with Luke Cage in charge of a group of unruly supervillains, not to mention a black ops squad similar to X-Force. It's possible elements from all those iterations will be adapted.
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