In the wake of Spirit Week, Imogen unearths long-buried truths on her path to unmask the mysterious "A." After Sheriff Beasley closes in, Noa, Faran, and Mouse weigh their options, while Tabby works to recover vital evidence.

Desperate to keep her mother's house, Imogen throws a Halloween party to raise cash – but the presence of an unwanted guest casts a shadow over the celebrations.