After spending an entire summer planning how to become popular and get Damen, her crush, to notice her, the unpopular Charlotte Usher's life seems to be looking up when Damen is made her Physics lab partner and asks for tutoring. However, her plans come to an unexpected end when she chokes to death on a gummy bear. Charlotte becomes a ghost, invisible to everyone she once knew, and forced to go to "Dead Ed" – a school for dead teenagers – to learn to use her supernatural abilities.
After some initial shock, Charlotte resolves to continue with her plan, using her new abilities to rejoin the living world, even though her Dead Ed classmates disapprove. While spying on Damen with his girlfriend Petula – the cheerleader Charlotte idolises – Charlotte discovers that Scarlet, Petula's goth sister, can see her. However, she is forced to leave to attend a meeting at the Dead Dorm, Hawthorne Manor, where the Dead Ed class are trying to prevent the manor from being sold. At Charlotte's suggestion, they disguise the building as unsafe to scare off buyers.
Inspired by her Dead Ed handbook, Charlotte attempts to possess Petula, but discovers possession is impossible without permission. Instead, Charlotte convinces Scarlet to allow herself to be possessed, gaining some time tutoring Damen in Physics while Scarlet enjoys making mischief as a ghost. However, Scarlet cuts the encounter short when Charlotte impulsively tries out for the cheer leading squad in her body. Charlotte possesses Scarlet again in order to attend a cheerleader slumber party, in return for allowing Scarlet to visit the Dead Dorm. While Charlotte decides that she is destined to share the "magical" Midnight Kiss with Damen at the upcoming Fall Ball, Scarlet is discovered by Prue and her interruption during a viewing accidentally causes Hawthorne Manor to be condemned.
Scarlet returns to the slumber party just as Charlotte is about to kiss Damen in a game of spin the bottle. As Prue uses her powers to scare away the other guests, Scarlet resolves not to be possessed again, but she is forced by Charlotte's promise to continue tutoring Damen. The pair begin to bond over similar tastes in music, and Scarlet's association with Damen makes her style popular. When Damen begins failing Physics, Scarlet, who has begun to like him, asks Charlotte for her help with the tutoring. However, the pair soon become jealous of each other, and decide to ask Damen to choose between them, only to be interrupted by Prue and the Dead Ed class.
As Charlotte is lectured to leave her old life behind her, she decides that if the Fall Ball,now cancelled after Prue's attack on the school, were held at Hawthorne Manor, the building would not have to be demolished – secretly planning to possess Scarlet on the night, as she is attending with Damen. The Dead Ed class agree and help decorate in a Halloween style, and Scarlet convinces the dance committee to change locations, reluctantly promising Charlotte the Midnight Kiss in return. However, Prue and the other Dead Ed kids crash the party, and Charlotte gives up her Midnight Kiss in order to stop them. When Scarlet and Damen are crowned king and queen of the dance, Charlotte surrenders the moment in the spotlight and achieves resolution. Charlotte and the Dead Ed class become visible to everyone, their wounds healed, and they join the dance before finally moving on.