The cast for Marvel's The Eternals keeps growing, as Angelina Jolie and Kumail Nanjiani have already been confirmed for the film. Now, it appears Train to Busan star Ma Dong-seok is also joining the upcoming Marvel Studios production.

According to The Wrap, the South Korean actor who also goes by Don Lee will make his American film debut in an undisclosed role in The Eternals. However, the outlet did note that Marvel had no comment on the casting.

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Dong-seok is for known for supporting roles in several South Korean films, including The Neighbor, Nameless Gangster: Rules of the Time and The Unjust, and his role in 2016's Train to Busan cemented him as one of the most bankable actors in South Korea.

As is the case with both Jolie and Nanjiani, Dong-seok's role is being kept heavily under wraps.

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Created by Jack Kirby in the 1970s, the Eternals are a race of superpowered, near-immortal beings formed by the Celestials. Although they've yet to appear in the MCU proper, their existence has been alluded to in the Guardians of the Galaxy films.

Directed by Chloé Zhao with a screenplay by Matthew and Ryan Firpo, The Eternals is expected to be released in theaters in 2020.