MALIBU, CALIF., JUNE 24 -- On Wednesday Tom Cruise will drive a race car in his new movie, "Days of Thunder"; today he went by car pool. He and his girlfriend, Nicole Kidman, and some other friends arrived at the second annual Entertainment Industry Conference on the Environment in one car, but most of the others had parked their BMWs and Jaguars and Hondas a mile away. Then they took not limousines but experimental propane "energy-saving" shuttles.

The conference was held on "sacred Indian ground" in Malibu, a place perhaps better known for mudslides and movie stars. There were plenty of the latter: Meg Ryan, Michael Keaton, Robert Downey Jr., Ed Begley Jr., Sondra Locke, Sarah Jessica Parker. Columbia Pictures co-president Peter Guber was supposed to show, but he jetted to his home in Aspen instead. Celebrity photographer Annie Leibovitz shot the event for Vanity Fair.

As the conferees trudged up a hill, they passed a sign reading: "Please Walk Softly on the Face of Mother Earth." As they topped the hill, they were greeted by a spectacular vision of the California coastline. In a basin just below, organizers had erected a large tent with straw on the floor and Indian spirit wheels hanging from the ceiling. Nearby booths offered fruits, organic sodas and tofu sandwiches -- along with Evian and Perrier waters -- to some of the 1,300 sweating people. Many of the conferees wore T-shirts from the organization sponsoring the event, ECO, or Earth Communications Office.

Started a year and a half ago by entertainment lawyer Bonnie Reiss, ECO has grown from a membership of 40 last year to about 1,200 today. That's 1,200 "actively committed" media workers and "50 to 80 top actors" dedicated to educating and organizing their entertainment industry into promoting environmentalism.

An example they relish is how the movie "The China Syndrome" affected the public's perception of nuclear power. More recently, there was the scene in "Lethal Weapon 2" when Danny Glover's movie family explains to Mel Gibson that they don't eat tuna because dolphins get caught in the nets. Cruise kicked the day off with an impassioned speech. "We must carry {environmentalism} into our lives, we must carry it into the streets if necessary," he said.

He listed a litany of environmental threats, from lead in drinking water to the soup of toxic chemicals in the air to the way bleaching paper white creates dioxin -- "the same stuff Vietnam vets are sick from."

Cruise was followed by a variety of informational and inspirational speakers, including presidential adviser Thomas Lovejoy, energy expert Hunter Lovins, farm activist Cesar Chavez and eco-feminist theoretician Riane Eisler. Chief Oren Lyons and Chief Leon Shenandoah spoke for the American Indian viewpoint, while Sens. John Heinz (R-Pa.) and Tim Wirth (D-Colo.) gave the view from Washington.

Most of the speakers addressed their remarks directly to the entertainment industry. Some took a light touch; Lyons ribbed his audience about cowboy movies. "How come the Indians never win?" he asked, then turned the joke into a lesson: "If you keep up that way, you're going to lose too."

Michael Klaper, stumping from the podium for a vegetarian diet -- or at least for the media to stop showing "the T-bone as an image of prosperity" -- also got a chance to settle a pet peeve. Why are tofu and bean sprouts always a gag on TV? "Vegetarians are connected with something noble, with respect for the land," he said -- to applause.

As the conference's self-described "token cynic," Michael Keaton brought a sense of irony to the day. "We preach to others," he said, "but the reality is we make more money and we have a lot more time. We should shoulder more responsibility."

Between speakers in the daylong conference, visitors were encouraged to tour "action booths" devoted to planting trees, recycling and conserving water. A fourth had a pledge form for people to sign promising to turn in their gas guzzlers for energy-efficient cars.

By the end of the day, at least some of the participants were ready to change their lives. Columbia Pictures public relations executive Mark Gill said he was determined to use a canvas bag for shopping and a water-saving bag in his toilet, buy coffee filters made of recycled paper, and buy bulk-size foodstuffs instead of smaller packages. He also sent in a postcard to have his junk mail stopped, and was considering writing his congressman.