Cameron Diaz star in ‘The Green Hornet’

Cameron Diaz is set to star in ‘The Green Hornet’.

The ‘What Happens In Vegas’ actress is favourite to take on the lead role opposite Seth Rogen, who will play the titular masked vigilante and his alter ego Britt Reid.

Few other casting announcements have been made, and although Stephen Chow was originally lined dup to play sidekick Kato, his involvement is now in doubt after his deal to direct fell through.

Instead, Michel Gondry will helm the project, with a script written by Seth and his writing partner Evan Goldberg.

Seth has previously revealed he is so dedicated to the project he has shed over 30lbs in preparation for the role – and admits his diet and exercise regime has left him emotional.

He said: "I’ve lost the weight for the role, but I don't know if I'll keep it off. That's the big question. I have a lot of tantrums. I want my food. I cry for no reason."

The actor is adamant he wouldn't have lost the weight if the film didn't require it and admits he feels like a "sell-out" for altering his body shape.

He recently said: "I'm selling out guys. It's the lamest thing ever. It's for 'The Green Hornet' - the only reason. There's no other reason. I just think it serves the movie."

‘The Green Hornet’ is set for release in July 2010.