NEW YORK (Reuters) - A tense new film shows Japanese fishermen luring thousands of wild dolphins into a hidden secret cove in Japan where activists say they are captured for marine amusement parks or slaughtered for food.

"The Cove" follows a team of activists including former dolphin trainer from the "Flipper" television series Ric O'Barry.

They battle Japanese police and fisherman to gain access to a cove in Taiji, Japan, where barbed wire blocks people from filming dolphin killings that begin in September each year.

The documentary opens in the United States on Friday but has yet to receive distribution in Japan, where O'Barry says 23,000 dolphins and porpoises are legally killed each year.

The Japanese government said it has done nothing wrong and cites cultural differences in response to the film.

Dolphin meat is eaten by a very small percentage of Japanese people.

The film has already been praised by critics and won the audience award at this year's Sundance Film Festival. "Eco-activist documentaries don't get much more compelling than 'The Cove'," said Variety's review.

O'Barry, who has been visiting Taiji several times a year for the past eight years and now wears disguises in the town to avoid the attention of fisherman and the police, predicted the film would have a big impact.

"When the film is seen in Japan, it will shut 'the cove' down permanently," he said in a recent interview.

The 69-year-old says he began fighting against the captivity of dolphins when one of the dolphins he trained for the hit 1960s television show "Flipper" voluntarily stopped breathing until it died.

"Ric is a hero," said the film's director, Louie Psihoyos, who has photographed for National Geographic magazine. "He had success, he had fame, he had money and he turned his back on all of that to follow his conscience."

LOS ANGELES (Reuters) - Her platinum white hair is long gone, replaced by silky smooth, dark brown locks. Yet that doesn't stop young girls from recognizing "High School Musical" star Ashley Tisdale at restaurants and asking for autographs.

Tisdale's role as Sharpay Evans, an over-the-top teenager who will stop at nothing to get what she wants in Disney's "High School Musical," has given her a huge following and altered Tisdale's life forever.

And the 24-year-old actress is expanding her career in new projects, including her role in movie "Aliens in the Attic," which debuts in U.S. theaters on Friday.

Tisdale continues to work in TV where "HSM" was a huge hit on the Disney Channel before becoming a movie, and she is even producing. Her singing has landed the actress a chart-topping recording career, and her second studio album, "Guilty Pleasures," comes out this week.

On the downside, her growing popularity has meant Tisdale has a constant trail of paparazzi following her around.

"I don't have a private life anymore; that's gone out the door," said Tisdale, but she has not let that stop her career.

In "Aliens in the Attic," Tisdale sheds her Sharpay image to portray a teen named Bethany, who joins other kids to battle aliens that land on the roof of her family's summer home.

Tisdale calls Bethany a "typical 17-year-old teen," whereas Sharpay tended toward being "very dramatic and very much a caricature." And Tisdale said getting away from "HSM" helps show her versatility as an actress.