With writer-director James Gunn already starting pre-production in Atlanta on Guardians of the Galaxy Vol. 2, the casting process has gotten under way as well. The Hollywood Reporter reveals that newcomer Pom Klementieff (Oldboy) has signed on for a mystery role in the highly-anticipated superhero sequel, which is scheduled to start production in February 2016. Variety also reports that Marvel and James Gunn wanted Oscar winner Matthew McConaughey to play the unspecified villain, but he turned down the role.

Insiders claim that a final decision on the villain role should be made within the next two weeks, but it isn't clear who the front runners may be, after Matthew McConaughey passed. The actor revealed in May that he has been offered both Marvel and DC Comics projects, but he wouldn't specify which scripts he read. It's worth noting that James Gunn didn't finish the script for Guardians of the Galaxy 2 until early June, so it's unlikely that this sequel is one of the projects he read for, especially after Variety's report claims that the actor only recently turned down the villain role.

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As for Pom Klementieff, insiders claimed that the actress seemed to have an "edge" with studio executives and the director, but it isn't clear what other actresses tried out for the role. The studio held a round of chemistry reads, with the role calling specifically for an Asian actress. Regardless of who she is playing, if her deal is finalized, Pom Klementieff will become the first new cast member to join Chris Pratt (Star-Lord), Vin Diesel (Groot), Zoe Saldana (Gamora), Bradley Cooper (Rocket Raccoon) and Dave Bautista (Drax the Destroyer) in the sequel.

James Gunn is directing Guardians of the Galaxy Vol. 2 from his own screenplay, with Kevin Feige producing. The director has teased plenty of story details throughout the past year, including that fans will get a definitive answer as to who Star-Lord's father really is, and it won't be the same character as the comics, J'son. The filmmaker has also teased that, since the first movie revolved around mothers, the sequel will center on fathers. With production about to start in a few months, hopefully new details will surface soon.

Pom Klementieff has mostly worked in France, starring in films such as Borderline, Sleepless Night and Delicacy. She made her American debut in 2013's Oldboy remake, where she played Haeng-Bok, a henchwoman for Sharlto Copley's character The Stranger. She most recently starred in Hacker's Game, which hit theaters back in March. Do you have any theories about who Pom Klementieff may be playing in Guardians of the Galaxy Vol. 2?