Young women will make or break the fourth quarter of this year for the movie business. There are three major Disney films that will rely heavily on turning out Females Under 25 and, of course, Summit unleashes the bookstore and internet sensation Twilight for Thanksgiving. The migration of Harry Potter and the Half Blood Prince to next summer has created an opportunity in the release schedule, and several of these girl-geared pictures are rushing to fill that gap.

There is no media company better at synergy than Disney. They popularized Miley Cyrus on the Disney Channel, then turned her into a box office sensation with the 3D spectacle Hannah Montana/Miley Cyrus Best of Both Worlds Concert Tour, which delivered  $31.1 million on its opening weekend and $65.2 million during the course of its domestic run. Disney's cross-platform promotional might will be on full display with its female-fueled fall slate.

It all starts with Beverly Hills Chihauhau, opening wide on Oct. 3, which features Piper Perabo (who's been a role player of late in films like Because I Said So and Cheaper By the Dozen) as caretaker for a mouthy dog in Beverly Hills. I am very high on this movie, and, in my estimation, it has a chance to be one of the big hits of the fall. It will play as a family film, and also, with voices provided by Salma Hayek, Andy Garcia, Cheech Marin, Edward James Olmos, George Lopez and Paul Rodriguez, it will do brisk business with Latinos. Ultimately, however, when you make a movie about the kind of dog that fits in a purse, you need Females Under 25 to show up in big numbers.

Disney follows with High School Musical 3: Senior Year. The HSM movies are already a phenomenon on the Disney Channel, and they should become a slam-dunk on the big screen as well, starting Oct. 24. 'Tweens, especially 'tween girls, are buzzing wildly about this one, and, keep in mind, the middle schoolers who watched the original High School Musical on cable in 2006 are now in high school themselves. The hype will only heighten as the release date approaches. The teens who read Perez Hilton are certain to get plenty of Zac Efron and Vanessa Hudgens news in advance of the release of HSM3.

Nov. 21 will bring Twilight (Summit) to America's multiplexes, based on Stephenie Meyer's young adult vampire novels. As Comic-Con attendees found out this summer, teenage girls will be falling over each other to see this film adaptation first. Think of it as Anne Rice for young females. Kristen Stewart (Into the Wild, In the Land of Women) has the lead role as Isabella Swan, but Robert Pattinson (ill-fated Cedric Diggory in Harry Potter and the Goblet of Fire), as tragic vampire hero Edward Cullen, will be the real breakout star. The question is, can this movie expand its reach beyond the book series' hardcore teenage female fans, to include the girls (and women) who have not read the books? That will be the job of the marketing folks at upstart distributor Summit, who have never had a hotter property on their hands than this.

Bolt (Disney) also debuts Nov. 21 and, although this is technically a family film, it is powered by Disney star Miley Cyrus, who provides one of the lead voices. This is a Digital 3D animated film that also features the voice of John Travolta, an actor many teenage girls know only as the guy in drag who played Tracy Turnblad's mom in Hairspray. Miley will be flogging this project everywhere from the Disney Channel to TRL on MTV to Ellen, so Females Under 25 are being counted on to show up in droves.

There are two other fall titles that are counting on younger women. Sony's Nick & Norah's Infinite Playlist is set for Oct. 3, with Michael Cera, in his first big role since Juno, and Kat Dennings (The House Bunny) in a PG-13-rated movie that looks to be in the tradition of John Hughes. Although teen guys will buy tickets as well, a high school relationship movie is probably looking for Females Under 25 to drive ticket sales.

Finally, Freestyle Releasing is handling The Haunting of Molly Hartley, to bow on Halloween. The film revolves around a 17-year-old girl trying to get a fresh start at a new high school, struggling to fit in while she deals with disturbing visions from the dark secrets of her past. Again, the PG-13 rating and a female protagonist indicate that young women will be called on to boost the box office take.