Azaleah's older sister Nia is going to be the star of the school musical but things keep going wrong at the rehearsals (missing batteries, disappearing props, microphones that suddenly do not work); Mr. Guidi, the director, blames the ghost of Thespis, but Azaleah suspects that somebody is actually sabotaging the play--and she is determined to use her detective skills to uncover the culprit, and set things right so the play will be a complete success for her stressed-out sister.