Some big-screen adaptations of TV hits don't demand any real knowledge about the show to enjoy them -- like, for instance, the South Park movie. Some, like the first X-Files film, do. Hannah Montana: The Movie, however, requires a pre-digested knowledge of, and unconditional love for, the titular pop princess. So as a service to everyone else, here's the sitcom's setup: typical high schooler Miley Stewart (Miley Cyrus) keeps a secret from everyone but her closest friends -- she's actually the superstar singing sensation Hannah Montana. She maintains a double life because she wants, as her theme song states, "the best of both worlds" -- the perks of fame and the anonymity of life outside the public eye. Hannah Montana: The Movie opens with Hannah's hectic lifestyle wrecking the important relationships in her life. Because she gets into a catfight over shoes with Tyra Banks, she forgets to say goodbye when her brother leaves for college, and she's late for her best friend's sweet sixteen because she's being chased by the paparazzi. Anxious to get Miley back to her roots, her manager/father (dadager?) (Billy Ray Cyrus), whisks her away to their hometown in Tennessee, where he hopes grandma and the locals will help the selfish star reconnect to some simple family values. Since Miley wants to be Hannah most of the time, she hates being stuck in the backwoods town, but a cute young ranch hand -- and her grandmother's love -- eventually melts her heart. And, when the town needs to raise cash to stop a developer from soiling their perfect little community with a big, evil mall, what celebrity performer do you think might just show up to save the day? The movie will undoubtedly satisfy the little girls who already love Hannah, although in many ways it's very different from the TV show. The actors aren't allowed to mug like they do on the small screen, and the absence of a laugh track accentuates the inherent lameness of the comedy. On the small screen, the show pops with energy, maintaining a ridiculous over-the-top tone, but the movie treats everything more seriously, while still trying for moments of outrageous physical comedy -- like an alligator biting Miley's brother, Jackson (Jason Earles), or the kids chasing a ferret around a fancy dinner party. It gives the whole thing a schizoid vibe, and director Peter Chelsom botches the slapstick scenes so badly that the movie just limps from scene to scene without building any momentum. Fans will clap along with the many songs, but the tunes aren't interesting enough to win over the unconverted -- a fact made clear when genuine teen star Taylor Swift shows up to perform -- she demonstrates all the spontaneity and authenticity that Miley Cyrus lacks. But Hannah Montana: The Movie isn't really about authenticity, it's about Miley Stewart learning to embrace both sides of her personality. And, while that may sound like an empowering lesson, it's the same one taught on just about every episode of the TV show. If you want to pay money for a longer, less fun version of what you can see for free, go right ahead.