Mark Ruffalo revealed via Twitter that he’s working with Andy Serkis on the Green Goliath in Avengers: Age of Ultron back in April, and now Serkis has announced that he’s not only consulting on the motion-capture effects for Joss Whedon’s hotly-anticipated sequel, but he’s in the movie.

His work as Gollum in The Lord of the Rings was the first time they filmed the mo-cap guy with the other actors on screen. His experience in the field of motion capture also includes The Hobbit, King Kong, The Adventures of Tintin: The Secret of the Unicorn, the Planet of the Apes and the upcoming sequel Dawn of the Planet of the Apes.

In a brief interview with Variety, the actor confirmed:

“I’m playing a role (in both films). On ‘The Avengers,’ I’ve been working closely with Mark Ruffalo.”

Serkis is also involved with Star Wars: Episode VII, but the actor who had plenty of live action roles as well wouldn’t specify whether parts are that of physical or mo-cap characters.

Marvel has yet to confirm if James Spader will be providing the voice and motion-capture work for the CGI-created evil robot Ultron or if any other new characters will be appearing.

Avengers: Age of Ultron is set for release in the UK on April 24th 2015 and North America on May 1st 2015, and sees Marvel veterans Robert Downey Jr. (Iron Man), Chris Evans (Captain America), Chris Hemsworth (Thor), Mark Ruffalo (The Incredible Hulk), Jeremy Renner (Hawkeye), Scarlett Johansson (Black Widow), Don Cheadle (War Machine), Cobie Smulders (Maria Hill), Samuel L. Jackson (Nick Fury) and Paul Bettany (JARVIS / The Vision) joined in the cast by new MCU additions Aaron Taylor-Johnson (Kick-Ass 2) as Quicksilver, Elizabeth Olsen (Godzilla) as the Scarlet Witch, James Spader (The Blacklist) as Ultron, Thomas Kretschmann (Dracula) as Baron Strucker and Josh Brolin (Oldboy) as Thanos.