Avengers: Age of Ultron fans are well aware of the work motion capture guru Andy Serkis is doing with Mark Ruffalo's Hulk performance, but Serkis' upcoming Marvel role remains less publicized.

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The former Gollum actor and Imaginarium consultant first teased his on camera involvement with Avengers at the end of June, but Serkis has remained tight lipped regarding his actual purpose in the Joss Whedon production.

Since all previously announced roles have already cast, fans must wait for either Serkis or Whedon to spill the beans on the upcoming character. In the meantime, Serkis dished out a few hints while speaking with The Daily Beast.

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"I'd have to deny that character at this point," Serkis said of the rumor that he will take Josh Brolin's Thanos role. "But I am playing a character. I was really thrilled that Joss Whedon asked me to be involved. It's fantastic. I've had a ball working with them, both as performance capture consultant through the Imaginarium, but also being asked to be in it. But I can't say anything more!"

Whedon and his Avengers crew are set to speak at the San Diego Comic-Con later this month, so perhaps Serkis' role will be revealed then. If not, fans may have to wait until Age of Ultron's May 1 release to get to the bottom of the matter.