AceShowbiz -

Stellan Skarsgard confirms he will return for "Avengers: Age of Ultron". He will reprise his role as Dr. Erik Selvig in "The Avengers" sequel. He will strip down in the upcoming flick, just like his mad appearance in "Thor: The Dark World".

"I'm going to do my fourth," he opened up to Total Film. "I'm going to be in 'Avengers: Age Of Ultron', a small appearance. It's something really nice. Even if it's owned by Disney now, it's really run by four or five people, and they know exactly what they're doing."

"I like working with them because if I have a problem with the scene, I have Kevin Feige's number. I can call the head of the studio. You can't do that when you work on a normal Disney film or with Warner Bros or Paramount," the 63-year-old actor went on.

Of what to expect from him, he spilled, "Yeah, I was naked again. They called my agent and said, 'Do you think Stellan will mind being naked?' My agent laughed his head off. Yeah, I almost insist! Sometimes with a contract you get a nudity clause, which is fantastic."

"It's supposed to protect me from having my genitals exploited, which I doubt anybody would make a dime on," he joked.

The Swedish actor, however, refused to reveal a tidbit on the movie, "First of all, I don't know what I'm allowed to say. But usually they call me in if they need something explained. There's a lot of explanations to do when it comes to that universe."

Directed by Josh Whedon, "Age of Ultron" is due May 1, 2015. Robert Downey Jr. is back as Iron Man, Chris Evans as Captain America, Chris Hemsworth as Thor, Scarlett Johansson as Black Widow, Mark Ruffalo as Hulk, and Jeremy Renner as Hawkeye. The new members include Aaron Johnson as Quicksilver, Elizabeth Olsen as Scarlet Witch, and James Spader as Ultron.