You know grumpy, diminutive Danny DeVito from his television roles in the classic Taxi and the ongoing It's Always Sunny in Philadelphia, or from dozens of darkly comic films: The War of the Roses, Throw Momma From the Train, L.A. Confidential, and even Batman Returns (he was, no surprise, the very smarmy Penguin). But you may not yet know him as the voice of the grumpy, diminutive Lorax, the heart and soul of the just-released big-screen version of Dr. Seuss's classic fable about people so caught up in material consumption that they've cut down the very last tree.

The tale's apocalyptic warning is, sadly, just as important today as it was when Seuss penned the book in 1971--but so is The Lorax's encouraging message that each of us can do something to address environmental ills. Sierra spoke with DeVito as he was wrapping up directing a horror movie called St. Sebastian.

YOU PLAY THE LORAX, DESCRIBED BY DR. SEUSS AS "SHORTISH AND OLDISH AND BROWNISH AND MOSSY." WAS THE ROLE MUCH OF A STRETCH?
Not at all. It was right up my alley. Every part I've ever played has been described like that.

WHAT APPEALED TO YOU ABOUT THE ROLE?
The book has been in my house for years. I read it to all three of my kids. It's a wonderful story about morality and sustainability. It reminds kids that there are other living creatures on this planet.

THE BOOK IS PRETTY DARK, EVEN DOWN TO THE COLORS DR. SEUSS USED. IS THE MOVIE TRUE TO THE SERIOUSNESS OF THE ORIGINAL STORY?
The movie is more bright and cheery. The Lorax's world is great to inhabit. The subject remains tough, though.

THE MOVIE ADDS A NEW CHARACTER, A FINANCIAL TITAN WHO SELLS CANS OF FRESH AIR. IS THAT A REFERENCE TO THE RECENT BANKING CRISIS?
The directors opened the movie up to make it more impactful. After all, the Once-ler [the story's antagonist] is a good guy. He's just misguided, taken in by his commercial ability to make Thneeds ["a Fine-Something-That-Everyone-Needs," which required cutting down the forests].

THE ONCE-LER ULTIMATELY CALLS FOR INDIVIDUAL RESPONSIBILITY BY SAYING, "UNLESS SOMEONE LIKE YOU CARES A WHOLE AWFUL LOT, NOTHING IS GOING TO GET BETTER. IT'S NOT." DO CHILDREN THESE DAYS RESPOND TO THAT?
They do. They learn that everything comes from something, be it in a movie or around the house.

DO PARENTS APPROACH ENVIRONMENTAL ISSUES DIFFERENTLY TODAY THAN WHEN YOU WERE GROWING UP?
My parents believed that we had all the money in the world and all the trees in the world. Parents and kids are more aware now that there's more to life than just turning a buck. Dr. Seuss wanted us to wake up, take a look around, and see what's going on.

YOU GOT INVOLVED IN ENVIRONMENTAL ISSUES FAIRLY EARLY. YOU DROVE AN ELECTRIC GM EV1 IN THE LATE 1990S.
I had always loved the idea of a car that had no emissions, and then this wonderful car came along. It was quiet and fast and economical. Then the powers that be decided it wasn't good for the oil companies, and they took it away from us. [See DeVito's grumpy video, "Who Killed My Car?," at http://bit.ly/DDcar.]

NOW YOU DRIVE AN ELECTRIC NISSAN LEAF. BUT WHY NOT DRIVE A TESLA ROADSTER? YOU'RE A HOLLYWOOD STAR.
The Leaf is affordable. It's $35,000, and you can get tax credits and rebates. When you do the math, it's pretty inexpensive. And you don't ever go to a gas station or pollute the air.

ARE YOU ENVIRONMENTALLY ACTIVE IN OTHER WAYS?
I support anything that supports my kids and grandkids, like wildlife causes and Ted Danson's oceans group, Oceana. I hate to preach, but we have maybe 50 years to get this right. Are you hip to that? "I'm the Lorax. And I speak for the trees!"

WHAT'S YOUR ENVIRONMENTAL VICE?
I've overcome the gas-guzzler thing, but I still need to learn to use less electricity. I want to install solar panels.