Seth Rogen and Cameron Diaz gear up for action and lots of laughs in the new action-comedy 'The Green Hornet,' in theaters January 14 in 3D and IMAX 3D, and Seth jokes to ET's Nancy O'Dell that he lost "800 pounds [for the role]."
"It wasn't that difficult, honestly. I think I was so unhealthy before that just by becoming incrementally healthier, the pounds washed away," he says. "It sucked. Eating well, that's a nightmare. Who wants to eat healthy food all the time? I mean, it's like insane."
In 'The Green Hornet,' Seth plays Britt Reid, a rich, spoiled playboy who is heir to L.A.'s largest newspaper fortune. Britt teams up with resourceful company employee Kato (Taiwanese artist Jay Chou) to do something worthwhile, and armed with the help of his secretary Lenore Case (Cameron) and the weapon-packed Black Beauty vehicle, The Green Hornet and Kato battle chief underworld criminal Benjamin Chudnofsky ('Inglourious Basterds' baddie Christoph Waltz) and his united army of gangs.
"I think not a lot of people knew about the Green Hornet, and that's what made it exciting," says Seth. "It left a lot of room for interpretation and we could kind of take a lot of liberty to update it and make it fun for today's audiences." He adds with a laugh, "It's the first d-bag superhero. It's about time that they got one."
"Seth's really great at playing a total idiot who you love," says Cameron with a nudge.
"I get it in real life a lot, too," jokes Seth.
Seth says that wooing Cameron for the role felt like both he and director Michel Gondry were going on a date with a girl. "We both want kind of want to impress her, and we both have to win her over," he says with his trademark laugh. "It was pretty funny."
"It was really cute," says Cameron, who shrugs it off, saying, "I didn't really need to go. They had me at 'Hey.'"
On a personal note, Cameron took a moment to slam the paparazzi for invading her privacy recently, in which she was spotted having fun in the sun with rumored beau Alex Rodriguez in Hawaii.
"I think it's the rudest thing ever to take a picture of a girl in a bikini from whatever angle you decide," says Cameron. "It's not okay."
Watch ET for more fun with the stars of 'The Green Hornet,' which opens January 14.