Amber Tamblyn is adamant that her new movie, The Sisterhood of the Traveling Pants, which opens tomorrow, is not a chick flick.

"The storylines are not about girls sharing tampon boxes," she says in a hotel suite overlooking Logan Square. "It's stuff about cultural diversity and families and sexuality and death. Stuff like that transcends age and gender."

The film takes its title from Ann Brashares' popular novel, which has become a must-read for today's girl. "Obviously the title is goofy. We know that," says Tamblyn. "But the movie's not much about a sisterhood. Or about pants. So it's kind of misleading.

"Traveling pants - people always assume that they're magical and move around on their own," she continues. "I'm like, 'No, they're symbolic of friendship. All they do is segue scenes."

In the film, Tamblyn, 22, plays Tibby, a dour aspiring filmmaker. Over a summer, she and her three lifelong friends, played by Gilmore Girls' Alexis Bledel, Blake Lively and America Ferrera, face a panoply of challenges, alone and together.

If TSOTTP isn't a chick flick, it certainly sounds as if making it was one long bachelorette blast for its four young stars.

"In between takes, we would go into the makeup trailer and choreograph dances for songs like 'Ice Ice Baby,'" says Lively, 17, who's on the road with Tamblyn. "We were just psychotic. The hair and makeup trailer was a crazy wild party at all times - music blasting, dancing, singing. We just had a ridiculous amount of fun."

At the moment, however, Tamblyn's mood is more subdued. She's been working without a break for two years, filming TSOTTP between seasons of her CBS series, Joan of Arcadia, in which she played the title character, a girl with an intriguing and vernacular relationship with God. Tamblyn was nominated for a lead-actress Emmy.

As the Memorial Day weekend kicked off, she was wrapping up a two-and-a-half week press tour for the film. In the middle of that junket, just after a season finale in which Joan was approached by the devil, CBS announced that it was not renewing the series for a third season.

"It's been very hard being on this tour in the last week," says Tamblyn. "Kids come running up to you and they love the show and they're like, 'What's going to happen to Joan and the devil?' You go, 'Well, honey, you're going to have to make that one up for yourself. However you want it to end is where Joan will be.' "

She seems to be taking the cancellation in stride. "I'm not sad or devastated," she says. "I'm just proud that I was part of something that was so incredible for two years as opposed to being on a show that was not so good for 10."

With TSOTTP, Tamblyn completes the acting trifecta. She's now starred on daytime TV, prime-time TV and in films. She is still most recognized as Emily Quartermaine on ABC's General Hospital, a role she originated at 13.

Her early start is remarkable given that it was the last thing her father wanted. "I had been a child actor, and I lived with Dean Stockwell who was a child star," says Russ Tamblyn, a Hollywood lifer who has appeared in everything from West Side Story to Twin Peaks. "I was against my child being an actor," he says by phone from California.

But after Amber's precocious school performance in Pippi Longstocking, Russ Tamblyn's agent was begging Russ to let her send the girl out on auditions. General Hospital snapped her up.

"I was young and crazy and rambunctious and I didn't listen or pay attention," says Tamblyn of her early years on the soap.

Hospital hunk Tyler Christopher, Eva Longoria's ex, who plays Nikolas Cassadine, agrees. "I was 23; she was 13 and we were playing almost the same age," he says in an interview from the soap set. "It was awkward in the beginning, especially when they wrote us a kissing scene. Her father, Russ, was always on stage" to comply with child labor laws.

"The scene called for her to surprise me," Christopher continues. "When it came time to lay the kiss on me, she really went for it. I was shocked out of my shoes. Russ was standing 15 feet away. At that point I knew this girl had guts."

Acting is only one of her interests. While she was on GH, she gained regional notoriety as a break dancer. Tamblyn is also an accomplished poet, appearing regularly at Los Angeles area poetry slams. Simon & Schuster is publishing a collection of her verse this fall.

Her artistic leanings are hardly surprising given her upbringing in Santa Monica. Her father was part of a tight-knit pack of bohemians that included actors Stockwell and Dennis Hopper, musician Neil Young, beat poet Jack Hirschman, and filmmaker David Lynch.

"I have like eight godfathers and they're all famous," she says. "Men who have influenced me and been very close to my family."

According to her father, none of them is responsible for Tamblyn's appreciable acting talent. "It's something you can't teach," he says. "It comes from a deep natural place. It was always there with Amber. She seemed to be able to reach down and pull it out of herself."

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