On the set of ABC’s summer drama “Mistresses,” premiering June 3, steps were taken to make the production as green as possible. “We have no [disposable] water bottles, we have canteens,” says executive producer K.J. Steinberg. “We recycle, we don’t print out sides for everybody unless they ask for them. There’s e-mailing of scripts, repurposing sets.”

The cast is happy to oblige. “I carry a little mug with me all the time,” says Yunjin Kim (“Lost”), who on set and off recycles and eats no red meat. “I’m kind of obsessed about it,” she says, noting that climate change and its repercussions scare her. “It’s a huge alarm going off for all of us. Look at the weather — it’s not normal. We need to take this to heart and make sure that for the next generation and those coming after, we need to take care of this earth.”

Jason George (“Grey’s Anatomy”) is equally diligent about reducing his family’s carbon footprint. “We switched to green power. It costs a bit more but I got three kids and I want to make the world better for them,” says the father of an eight-year-old son and twin four-year-olds, a boy and a girl. “I’m trying to get them to understand that everything you do makes a difference. So we turn the lights off. I’ve been ‘Captain CFL’ for years. It just makes sense—it saves money.”

Alyssa Milano, who many still think of as the cute kid from “Who’s the Boss?” is a 40-year-old mom now and a charity-minded one at that, supporting PETA, UNICEF and Charity Water, which builds wells in Africa; She contributes every year via a fundraiser on her birthday. So far, she’s helped to build 20 wells in Ethiopia.

Milano was attracted to the series -- which is about four friends involved in relationships in which one of the parties is betraying a spouse -- for the chance to play a flawed character. “She’s a really nice person that made a really bad decision and is paying for that,” Milano says of her married lawyer character, who cheats with a colleague (George). She likes being part of an ensemble for the lighter work schedule that allows her more time off with her son, and the camaraderie that the premise provides. “The core of our show is that friendship between the women, and no matter what situation that we get ourselves into by some poor choices that we make, we have the support of our friends.”

Kim plays a therapist who violates a cardinal rule by having an affair with a married patient. “There’s something really dark, juicy and wrong about my storyline that I love,” says the Korean actress, who returned to Korea when “Lost” ended and made one film after another until “Mistresses” brought her back to Hollywood. “As soon as I read it I fell in love with it,” she says of the script. She was married two years ago, to a Korean producer, and although her husband is #1 in her life now, she emphasizes the importance of having girlfriends like the characters on the show “They’re my rock,” says Kim of her pals. ”They’ll hold me to the ground and they’ll tell me the truth.

George was eager to take on the part of Milano’s paramour, though it required a bit of stretching. “He’s a passionate dude, a flirt. I had to research the flirt part, base it on people I know.” First interested in acting as a second grader, he put it aside to follow an academic path that would take him to law school. “But I took an acting class my first year of college and it all went out the window.” Besides playing Dr. Ben Warren in “Grey’s,” he has appeared on the TV series “Eli Stone,” “Platinum,” and “Off the Map,” to name a few. ” In the future, he would like to tackle a dramatically meaty role “like ‘Breaking Bad’ or Denzel’s [Washington] in ‘Flight,’ where a regular person is put in extreme circumstances.”

Under the covers with ABC's 'Mistresses'
How Yunjin Kim, Alyssa Milano and Jason George keep it green on the set of ABC's new drama.