Unconvinced she's dead, an invisible Maddie searches for clues to her disappearance and encounters other teenage ghosts trapped at her high school.
Maddie suspects her boyfriend could be behind her disappearance and enlists the help of an unexpected ally to fill the gaps in her memory.
Maddie grapples with her own secrets when a second suspect emerges. Vandalizing the school with her new ghost friends allows her to blow off some steam.
Maddie turns to her ghost friends for help, but their investigation into the latest suspect puts Simon in the hot seat with the police.
While Split River High's potential homecoming queen emerges as a suspect, Maddie ponders the effect her disappearance has had on her mother.
Maddie and the ghost gang hatch a risky plan to trick Claire, her former friend and popular cheerleader, into a confession at the homecoming dance.
The ghosts try to help Maddie recall her memories of the day she disappeared, while Simon and Xavier sneak into the sheriff's office to peek at evidence.
Maddie and her friends — both living and dead — can't help but feel they've been lied to, and they demand answers from the adults around them.