On the surface, Fox's new series "Terra Nova" is an ambitiously epic action adventure complete with CG dinosaurs, but the Steven Spielberg-produced series has an environmental undercurrent. It's set in 2149, a future when the air isn't breathable, plant and animal life is extinct, and the only refuge from a ravaged planet comes to lottery winners via a time portal to an unspoiled Earth millions of years in the past, where a new settlement gives them a chance to correct mistakes and start over.

"We're not specific about what happened. Was it global warming? As the series goes on we make some references to wars. But we're not adhering to any one theory about how the world is going to get screwed up. It probably was a lot of things," says executive producer Brannon Braga. "This is a scary vision of the future, a worst-case scenario, what happens if we don't do anything about it now," says star Jason O'Mara. "Earth is dying, because we are on the present course that we've already set. Climate change, we didn't recycle fast enough, and we didn't switch over to electric cars fast enough and we're still burning oil," enumerates the actor, adding that "the environment was already a hot issue for me" when he signed on to the project.

The Irish actor, seen most recently on American TV in "Life on Mars" plays ex-cop Jim Shannon, who escapes prison to join his wife and kids in the new settlement, which initially seems like paradise. "It's like your first night in a hotel. You get there and you think, 'Oh, this is fantastic,' but after awhile the room service is cold, it's not what it's cracked up to be. Your view isn't so good," he compares. "There's something going on, everything isn't quite what it seems."

O'Mara, who plays another cop opposite Katherine Heigl in "One For the Money" this January, is enjoying the action aspect, playing the kind of scene that recently required him to hang upside down for three hours fighting off dinosaurs. But it's been admittedly difficult for him to leave his family behind to film in Australia, where steps are being taken to keep the production green.

"We found a ranch in Queensland where we could build our town without disrupting anything," says Brannon Braga. "In the surrounding forest we film in, we're very careful to not do any damage. We want to keep it alive and beautiful. Fox is a green company and it's very much a green show," adds the producer, noting that the production office uses water jugs instead of disposable bottles and transmits scripts electronically ("I read mine on my iPad"). Considering the message of the show, he says, "It would be kind of outrageous if we weren't conscious in our daily lives."

"Terra Nova" premieres Sept. 26 on Fox.

Check out our celeb section and watch Ecollywood videos.

"Dolphin Tale" has an environmental message >