Matt Damon agreed to star in Terry Gilliam's new movie The Zero Theorem without even reading the script, the director has revealed.

The Monty Python star shot the science fiction drama on a minimal budget, in Romania, in just 36 days. The science fiction drama stars Christoph Waltz as a reclusive computer programmer trying to crack a formula that will reveal the meaning of life, and boasts an all-star cast including Matt Damon, Tilda Swinton, David Thewlis and Ben Whishaw.

Gilliam confessed: "That was the surprisingly easy bit because suddenly I discovered there were people out there who liked me.

"I called Matt [Damon] and said I've got a small part for you, probably four or five days, I'll send you the script. He said, 'Don't bother, I'm in.'

"People like Tilda - we had met at different festivals and always said we ought to work together, Ben Whishaw the same thing. And basically I just called them and they all just came and they worked for scale, that's how we made the film, because we didn't have the budget.

"Tilda came and did all of her stuff in one day. The doctor scene with Ben and Sanjeev Bhaskar and Peter Stormare, one day.

"And you realise that over the years you've worked with people and they're happy to come and play."

The film, which opens in cinemas on Friday March 14, also stars French actress Melanie Thierry as femme fatale Bainsley. Jessica Biel was originally linked to the role, but Gilliam admits he went against the studio's pressure that he cast a big Hollywood star in the role.

He said: "All the names I saw were American and they all have become very much alike. There's a certain American quality in actresses, and I said, 'No, there's nothing surprising there.' They're fine, they're good, there's no question about that, but there's no surprise.

"I've always loved French actresses because they have a very different approach to life. And a friend of mine suggested Melanie, and she sent a tape in and she was just terrific. I said 'That's who we want, got to have her', and I just dug my heels in, that's all."

Meanwhile Gilliam admitted he hopes to start filming his Don Quixote film this year - 15 years after he first began work on the project.

The Imaginarium Of Doctor Parnassus director said he hopes to begin shooting The Man Who Killed Don Quixote in Spain in September.

Gilliam said: "It's my default position basically! So we're trying to do it again, I'm hoping this year.

"I've got a young Spanish producer - 29 years old - he doesn't know better! But he started producing films at 24, remember the film Buried with Ryan Reynolds, that was the first film he produced when he was just a kid, so he's very bright.

"So I've been down-looking locations again. We always rewrite it, each time I start again we do rewrites and change it. So I wouldn't say it's exactly autobiographical but it incorporates life that I've lived.

"I don't take time any more, I just go for it. I've lived with it too long - the best thing is to jump in.

"That's in a sense what happened with Zero Theorem, we only had two months from Christoph [Waltz] saying yes to start shooting. And that is not enough time to build the world we created and all that, but we did it.

"You have to work on instinct, which I really do enjoy, because if given the time and money I will double things into infinite oblivion."