Marvel has cast Will Poulter (The Revenant, Detroit) as Adam Warlock in is set to start filming later this year, ahead of its release date in 2023.
Marvel is being typically secretive about the plot. Still, it's generally been assumed it will pick up where Guardians of the Galaxy Vol. 2's post-credits pointed to the introduction of the MCU's Adam Warlock, one of the most powerful superheroes in Marvel's comic book universe.
Now, with production on Guardians of the Galaxy Vol. 3 soon to begin, Deadline has confirmed Marvel Studios has cast Will Poulter (The Revenant, Detroit) as Adam Warlock. Apparently, Marvel conducted a lengthy search to find the right actor, with Poulter and several other actors called in for auditions. Since late August, James Gunn and Marvel execs have reportedly discussed this and eventually decided Poulter's test was too good to on. The reports have been confirmed by James Gunn himself, who welcomed Poulter to the team on Twitter.
When the Guardians of the Galaxy made their big-screen debut in 2014, they were unlike anything comic book readers had seen before; Gunn seems to be taking the same kind of creative, inventive approach with Adam Warlock because Poulter doesn't feel like the comic book character at all. But then, the MCU's Adam Warlock will be so very different from the comics; there, he's a super-evolved human being, and he became bonded with the Soul Stone. The Avengers: Endgame, meaning Adam Warlock's most significant comic book arc can't happen in the MCU, and with Thanos having been killed when Tony Stark snapped his fingers, Adam Warlock's greatest foe has already been taken off the table.
Guardians of the Galaxy Vol. 2 seemed to set Adam Warlock up as an antagonist to the Guardians, rather than as an ally; he was created by Ayesha as a weapon to be used against them, after all. Still, it's worth noting the space-faring superheroes may have had a power-up, given Thor has been traveling with the Guardians; Star-Lord may resent the God of Thunder, but he may well have good reason to be thankful for his presence in Guardians of the Galaxy Vol. 3.
Source: Deadline