Marvel's highly-anticipated Phase 4 sequel Avengers: Infinity War started production back in January. Even though filming has been under way for a few months, little has been revealed about the story. We reported in January that Peter Dinklage was being sought to play an unspecified character, with theories running rampant that he's playing either MODOK or Pip the Troll, neither of which have been confirmed. Today we have word that the movie has added another cast member, motion capture specialist Terry Notary, who will have a pivotal role.

The Hollywood Reporter caught up with Terry Notary, who was promoting his work as the title ape in Kong: Skull Island, which he performed via motion capture. He has also portrayed the ape Rocket in Rise of the Planet of the Apes, Dawn of the Planet of the Apes and the upcoming War For the Planet of the Apes, and Peon in last year's Warcraft. When asked about what he's working on next, Terry Notary said he is working with Josh Brolin for the motion capture work of Thanos, along with three other unspecified characters in Avenges: Infinity War. Here's what he had to say, confirming he is also playing the "right hand bad guy" to Thanos.

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"I'm working on four characters right now. I'm working with Josh Brolin and three other actors (in Marvel's Avengers: Infinity War), and I'm playing Josh Brolin's right hand bad guy in the film. I can't say the name of the character or I think Marvel will sever my head, but I apply those same principals of what it means to drop bulls--t and just play a character truly evil. And it's working. It's truly working."

While Marvel hasn't revealed an official cast list quite yet, a recent casting call mentioned several previously-established MCU stars that are returning for this movie. These actors include Josh Brolin (Thanos), Chris Hemsworth (Thor), Sebastian Stan (Bucky/Winter Soldier), Scarlett Johansson (Natasha Romanoff/Black Widow), Jeremy Renner (Clint Barton/Hawkeye), Chris Evans (Captain America/Steve Rogers), Elizabeth Olsen (Wanda Maximoff/Scarlet Witch), Samuel L. Jackson (Nick Fury), Paul Rudd (Scott Lang/Ant-Man), Paul Bettany (Vision), Chadwick Boseman (T'Challa/Black Panther), Mark Ruffalo (Bruce Banner/Hulk) and Robert Downey Jr. (Tony Stark/Iron Man), Chris Pratt, (Star-Lord), Zoe Saldana (Gamora), Dave Bautista (Drax the Destroyer), Karen Gillan (Nebula), Vin Diesel (Groot), Bradley Cooper (Rocket Raccoon), Benedict Cumberbatch (Doctor Strange), Benedict Wong (Wong) and Brie Larson (Captain Marvel). It was later confirmed that Tom Holland will swing by as Spider-Man, while another rumor surfaced that Liv Tyler could be returning as Betty Ross from the Phase 1 movie The Incredible Hulk.

The Russo Brothers are directing Avengers: Infinity War from a script by Christopher Markus and Stephen McFeely, who wrote all three of the Captain America movies for Marvel Studios. The filmmakers are also shooting Avengers 4, which is currently untitled, back-to-back with Avengers: Infinity War, with the first movie scheduled to hit theaters on May 4, 2018, with the untitled sequel arriving in theaters May 3, 2019. Terry Notary will next be seen in director Ruben Ostland's new film The Square, alongside Elisabeth Moss and Dominic West.