Paul Dano says filming 'For Ellen' made him ill.

The 28-year-old actor succumbed to a terrible fever while playing damaged rock singer Joby in So Yong Kim's new drama because he had to wear tight skinny jeans and pointy boots in snow-covered New York.

He said: ''That outfit did not cut it. I got a throat infection. We were filming for three weeks and I got a steroid shot in my butt to push myself through my fever.''

Paul enjoyed playing a father locked in a custody battle for his daughter and found it humbling to have to look after the young actress who played his daughter, Shaylena Mandigo, on set.

He explained: ''It was amazing to put on the tight pants and boots and feel like the character. Some people don't like working with kids, but kids keep you honest. If you're crossing a street in a scene you can't be the selfish actor. You have to be in the moment so this little girl isn't hit by a car.''

The actor boasts a varied resume filled with both blockbuster hits like 'Looper' and smaller independent roles, but the only factor that motivates him to take on a new role is whether he likes the director.

He said: ''Indie or mainstream isn't the choice I'm making. Obviously I've got to make sure my bills are paid. It's whether I want to work with a director. There's got to be some exciting creative sparks.''