Sharpay's Fabulous Adventure is a spin-off movie of the High School Music series of films. It begins with Sharpay in a dance routine at the Lava Springs Country Club, meeting the famous producer Jerry Taylor. Taylor offers a shot at stardom in his newest Broadway show (however, the offer is for her dog, Boi). Sharpay asks her father to let her live independently in New York City. He hesitates but allows her to do so, however, if the plan fails, Sharpay is to return home and work at the country club. Having moved to New York City, Sharpay is booted from her penthouse apartment due to a "no pets allowed" policy. Desperate, a man known as Peyton offers to let her live in a studio apartment. Sharpay, Peyton, and the dog go on a shopping spree to decorate the place.
To raise her spirits, Peyton brings Sharpay to the Radio City Music Hall. Sharpay encounters the producers of Jerry's show and learns that the shot at stardom was for Boi. Sensing she still has a chance, Sharpay auditions and is evenly talented with Roger Elliston. A short while later, Sharpay meets show star Amber Lee Adams. As she leaves the theater, Sharpay is told by Roger to drop out, or suffer serious consequences.
Later on, Sharpay and Roger's dogs run off together, forcing the rivals to join forces to find their pets. Peyton discovers the dogs at the theater. Elsewhere, Amber Lee fires her assistant and hires Sharpay, just so Amber can boss her around. Shapray winds up serving as Amber's maid, with she and Roger joining forces to get Amber fired. The plan works, but Sharpay is also fired. As all seems lost, Peyton shows the producers footage of Sharpay's musical prowess. The producers agree and hire Sharpay as the lead role. Sharpay agrees, but only if the two dogs are allowed to share the canine role. Sharpay and Peyton kiss and she gets to finally perform on Broadway.