NEW YORK - Parents hoping to purchase tickets to the Hannah Montana movie may be in for a tough time.

Hundreds of showtimes are already sold out on Fandango and theater owners are constantly adding new ones, says Harry Medved, spokesman for Fandango, the nation's largest movie ticketing service. The movie opens nationwide in the U.S. Feb. 1 and runs for one week only. Tickets went on sale Dec. 1 and can be purchased online or at the box office.

"We have 21 girls in our Girl Scout troop and I wanted to be able to offer it to all of them, thinking it would be great if we could go together," said Patti Feurman, mother of two in Ridgefield, Conn. "It was impossible to get that many tickets for a single show. We all had to break up to try to find tickets and we are all at different showtimes."

"Hannah Montana & Miley Cyrus: Best of Both Worlds Concert" captures singing sensation Miley Cyrus during her 54-date tour. In the movie, Miley, 15, star of Disney Channel's "Hannah Montana" series, performs as both a solo artist and as her television character, Hannah Montana. The movie is in Disney Digital 3D.

The concert movie was the No. 1 seller on MovieTickets.com its first week on sale, selling more on that Friday, Saturday and Sunday, than any other movies for the entire week, said Joel Cohen, MovieTickets.com's executive vice president and general manager. He says the ticketing service has sold thousands of tickets each day since.

The film was 30 per cent of the ticket sales on Fandango as of Thursday, right behind "Cloverfield," which comes out Friday, and has consistently been a top-selling ticket on the site, says Medved. A Los Angeles movie theater had a 12:01 a.m. Feb. 1 showtime, with other theaters starting around 8 a.m. that day. The movie is playing in more than 600 theaters.

"It's the best-selling concert movie in Fandango's seven-year history," said Rick Butler, chief operating officer of Fandango.

Despite the slight headaches, some parents say the movie makes up for some of the disappointment their children felt when Miley's "Best of Both Worlds Tour" sold out within minutes of when the tickets went on sale.

"I think the movie is going to be something special for the kids who didn't get to see the concert," says Patricia Garrett, of Anaheim, Calif., who unsuccessfully tried to purchase concert tickets to take her 9-year-old daughter.

Disney declined to comment on why the movie is out for only a week and would not say whether the film's run would be extended or if it would be released on DVD.

It's not unusual for a movie to come out only out for a week.

Mary Dalton, associate professor of communication at Wake Forest University, says some religious films were released in a similar fashion years ago. These days, she says some small films might play in Los Angeles and New York for a short time to qualify for Oscar nominations, and many other films are test-marketed for a few days without having a larger release later.

"The Hannah Montana movie is really more like big-screen television and less like conventional movies," says Dalton, who teaches film. "The idea is to get people to come out at a certain time and see the film."

Maria Bailey, who flew her two daughters across the country to meet Miley, says the one-week only movie is actually a "gift" for most parents.

"It comes and it goes quickly," says Bailey, also author of "Trillion Dollar Moms: Marketing to a New Generation of Moms." "It prevents the market from getting over saturated with Hannah Montana-ism."