Chris Hemsworth pushed to be funnier by Thor: Ragnarok director's insults

Chris Hemsworth forced himself to improve his improvisational skills on the set of Thor: Ragnarok after fielding insults from director Taika Waititi.

The Australian actor reprises his titular role as the Marvel superhero in the new movie, but this time around, Chris and Taika wanted to give the franchise a big injection of humor to lighten the mood of the film and make it more appealing to fans.

Taika allowed Chris and his co-stars, including Tom Hiddleston, Cate Blanchett, and Jeff Goldblum, to practise their comedy skills as the cameras rolled, but he made sure to call them all out when something didn't quite work.

"It was the first thing, when Taika and I spoke about it (direction of the movie), I said, 'I'm sick of me (as this character),' and he said, 'I'm sick of you, too... so what can we do differently?'" Chris recalled on breakfast show Good Morning America. "So every day, if it (dialogue) felt familiar, we just went in a different direction. Huge improvisation.

"Taika would stand off-set, kinda (sic) yelling suggestions, and commentating on your performance. Sometimes, (he'd shout), 'That sucks! Don't do that again!'."

Part of the franchise revamp also involved giving Thor a new look onscreen - including chopping off his character's trademark long, blond locks.

"I just got sick of spending two hours in hair and make-up putting the wig on every day!" Chris joked, before explaining, "It was just kind of part of this rebirth, this reinvention of the character, to strip it all away: break his hammer, cut his hair, change the costume, change the music, and it did, it gives it such a different flavor, and 'cause of that I think the improvisational quality has a very unpredictable, wacky nature to it, which is unique and something we're all pretty proud of."

The gamble appears to have paid off as Thor: Ragnarok, the third film in the superhero franchise, has received glowing reviews from critics, with many branding it the best of the trilogy, which began with 2011's Thor, and its sequel, Thor: The Dark World, in 2013.