Nellie spends detention in the "crypt." Meanwhile, Chloe goes on an impromptu date and the entire school faces backlash when Nick's "study pills" are uncovered. 

It may be the season finale, but the mystery is far from over. Nellie, Chloe, and Tiffany work together to uncover a long-held Crown Lake secret that could change everything... but, will it be enough to reveal Heather's identity and stop her, once and for all?