“Mistresses” 10 p.m. Monday, ABC

ABC’s sexually-charged summer series “Mistresses” has many secrets. But they’re nothing for actress Yunjin Kim’s compared to the mysteries she faced as Sun-Hwa Kwon on “Lost.” Even the way the new drama’s filmed is a complete change for the actress.

“It’s refreshing to get scripts through emails, something that was never done on ‘Lost,’” Kim said. “There are no blank pages, polar bears, a mysterious hatch or all that.

“It’s really refreshing to do a show that’s about the simplicity of life, love, relationships and friendship.”

“Mistresses,” based on the BBC series, features Kim, along with Alyssa Milano, Rochelle Aytes and Jes Macallan, as a group of girlfriends on a path of self-discovery. Kim’s character is a therapist who reconnects with her friends after a relationship with a married patient goes too far.

The full script, which Kim got to see in advance, left her speechless at times because of all the mistakes her character makes.

“The other women aren’t really mistresses. My character is THE mistress of the show,” Kim says. “When you first meet her, she’s already been a mistress and she loses the love of her life. I really am playing an awful character. My character’s not just crossing personal issues, but professional issues as well.”

“Mistresses” takes Kim in a completely different acting direction than “Lost.” She wasn’t looking for her new TV project when “Mistress” came along, but she knew it was the kind of project she wanted to do.

“I’m surrounded by amazing women,” Kim said. “To do a show about amazing friends that I can understand and relate and sympathize with is a great thing.”