Editor's note: This week's Ecollywood column was so long that we had to cut it in half. Read the other part, about our star-studded red carpet coverage of the Oceana gala event.

While he’s just joking when he says he works by candlelight to save energy, Zac Efron is serious about one aspect of green living. “I don’t use water bottles anymore at my house. I have a water filter,” said the High School Musical alum, who stars in the excellent period film Me & Orson Welles as a teenager cast in a bit role in Welles’ 1937 modern-dress staging of Julius Caesar at his Mercury Theater in New York. Efron jumped at the “unique opportunity” to do something different. “It came at the perfect time,” he says, hoping that the movie, which was adapted from a novel loosely based on a real member of the Julius Caesar cast, sparks an interest in Welles among his young fans. Efron’s next release is the title role in The Death and Life of Charlie St. Cloud, a teen grieving over the death of his younger brother.

Claire Danes (pictured right), who plays Welles’ assistant Sonja and love interest for Efron’s Richard, liked the idea of a character who’s “bright and ambitious and for the time, pretty brazen.” A New Yorker, Danes recycles and relies on public transportation to reduce her carbon footprint. “I don’t even have a car,” she notes. A lesser-known real-life figure is the subject of Danes’ next project -- she plays Temple Grandin in an HBO movie (due to air in February) about the autistic woman who became a scientist and animal rights activist.

Portraying the arrogant, brilliant genius that was the young Orson Welles is British stage actor Christian McKay, who’d played Welles on stage but never thought he’d be cast. Indeed, potential backers wanted a Hollywood name, which is why director Richard Linklater, adamant about his choice, went to Europe for financing. “I’m the only actor in the world that had to lose weight to play Orson Welles,” says the tall Englishman, who gives an Oscar-worthy performance. “I’m enjoying the ride, but I don’t expect it,” he says of a potential nomination.

McKay (pictured left), who drives a hybrid, learned about recycling from his wife. “She’s Australian and grew up with it,” he explains. With a small role in Woody Allen’s next film and the part of an MI6 agent in Mr. Nice, about drug smuggler Howard Marks, he’s calling a moratorium on Welles for now but would consider revisiting him in 20 years, when he’s old enough to play the icon at the end of his career -- and when no dieting would be required. “Just bring the chocolate,” he chuckles. “That would be the greatest preparation for a role.”

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Tune in: Planet Green will air Al Gore’s Oscar-winning global warming documentary An Inconvenient Truth on Nov. 25 and Nov. 28.

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