Tom Hiddleston thought he was "rubbish" in Thor.

The 31-year-old star feels "very lucky" that director Joss Whedon enjoyed his performance as Thor's (Chris Hemsworth) brother Loki in the Kenneth Branagh-helmed superhero movie, so much so he wanted him to play a big part in The Avengers.

"There was no guarantee that it was going to be such a big part, I think. And I also felt like I'd been rubbish in Thor - there was no way I was going to come back. So it was one step at a time and I was very lucky that, as we were coming to the end of shooting Thor, Ken Branagh showed Joss a rough cut of the film and Joss loved it, he loved what Ken had done with it and was really about what Chris and I had done on it. And [Whedon] said, 'I want to take that relationship and make the stakes higher. You've got these two brothers who are fighting each other and now what's at stake is the fate of Planet Earth, because that's what's going on.' So it's really exciting."

Tom couldn't believe his luck when he read how much of a big role Loki had in The Avengers - which sees the Asgardian and his army attempt to take over the world - and he admits the part was as "damaged and psychologically interesting" as he'd hoped for.

"I never get afraid of things, I only get excited. It's just so much fun, he's such a great character, never mind the iconography. The film is called The Avengers, and yet Loki was on almost every page. He'd taken what I'd built with Kenneth Branagh and he'd taken it further and it was as damaged and psychologically interesting as I hoped it would be, but it was also darker and funnier and demanded so much commitment," he added.