The “Slumdog Millionaire” star will play an integral supporting role, while the French actress has been cast as a villainess
(Update 2 p.m. PST: "Slumdog Millionaire" star Anil Kapoor is in negotiations to play yet another villain in "M:I:4" according to Deadline, though Paramount claims the character isn't a villain, and Kapoor will simply play an "integral supporting role" that is being kept under wraps. Kapoor was last seen on the final season of Fox's "24," and he is represented by ICM.)
Seydoux, who has appeared in "Inglourious Basterds" and "Robin Hood," was one of the rumored contenders to play Lisbeth Salander in David Fincher's English-language adaptation of "The Girl With the Dragon Tattoo."
The fourth "Mission" is set to open on Dec. 16, 2011, and production is under way in Europe.
Seydoux is represented overseas by United Agents and Adequat.