Sam can barely contain her contempt for the "Miss Teenage Happy Princess" beauty pageant and its organizer, Dora Mattingly, when they descend on Casper High. She decides to enter the contest to make a statement about individuality, but makes a discovery instead: Dora Mattingly is the Dragon Ghost! Before she can get to the bottom of the mystery, she's inadvertently crowned Miss Teenage Happy Princess by its happy-go-lucky judge... Danny Fenton! When the tiara is placed on Sam's head, it magically transports her to a castle in the Ghost Zone, where she learns she's to be the bride of Dora's brother, the ghostly Prince Aragon. As Danny and Tucker head into the Ghost Zone to rescue Sam, she does her best to shake things up in the medieval ghost world she's stuck in.