Academy Award-nominated actor Mark Ruffalo, who is set to reprise the role of Bruce Banner/Hulk in Marvel Studios' "Thor: Ragnarok", says it was fun for him to play two different characters.

"In this story Banner's been basically inside the Hulk for two years when we find him. During this time, all of the traumatic things in his life that have been making him afraid, making him doubtful, making him unable to enjoy his life, have been erased. His neurotransmitters and neuropathways have been completely re-wired. So when he comes awake, he's like an eight-year-old or 12-year-old boy," Ruffalo said.

The actor added: "He has the same exuberance and curiosity and wonder. He finally also realizes that he's free of the Hulk."

Describing Hulk's changes, Ruffalo said: "Hulk can be sad or happy. He's speaking. He's not only alive because of rage, so we can start to have more geography in the character's emotional life, his intelligence, what he does, what he eats, if he sleeps -- all the questions I've been dying to ask for years since playing this part.

"It's a different Banner and a different Hulk. So I get to play two totally different characters in this movie, which is really fun."

For Ruffalo, one lasting memory of working on the film was the welcoming ceremony by aboriginal natives at the start of production.

"Taika Waititi, the director, is a Maori. So the people who did the ceremony are his Maori brothers here in Australia. They came to bless the movie. I've been to Native American blessings for the climate march in America that we had a couple years ago. They're always beautiful and sincere and invigorating and lovely and communal," Ruffalo said.

The actor says he was excited to be part of the welcoming ceremony on this movie.

"There's a lot of wisdom in that culture that we could carry with us. It was really beautiful and moving. I do feel like we were blessed," he added.

"Thor: Ragnarok" is set to release on November 3.