The Avengers: Age Of Ultron trailer gave fans of earth's Mightiest Heroes their first look at a mysterious new character, but Marvel has yet to reveal the newbie's role.

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Actress Kim Soo-hyun/Claudia Kim was cast back in March, but a lack of details surrounding her character caused her to fall by the wayside. Her presence in the first trailer, however, proves Kim will play a larger role than originally believed.

"After a long wait, I'm happy to be back with great news," Kim wrote in March (translation provided by IGN). "I have a lot to do ahead of me, but for now, the words 'Welcome to the Marvel Universe' are amazing and kind of overwhelming. I was a fan of Marvel Comics, and if you really like something, looks like fate can make it happen."

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So who is this enigmatic new Marvel presence? Kim told The USA Today that she will portray "doctor/scientist who is friends with Tony Stark," and the site than posited that her character could either be SHIELD's AI Division head Monica Chang or a cybernetics scientist for Stark Industries named Suzi Endo.

It remains to be seen if the South Korean's Marvel persona is the reason Age of Ultron filmed in Seoul.

Find out more when Avengers: Age of Ultron hits theaters on May 1.