The game is afoot! Cat begins her investigtion with her best friend and podcast co-host, Allie. They look over Allie's super-helpful, super-pink suspect board, which ranks the other Liars Club members' alibis by how suspicious they are. They realize that Naia's alibi is really weak. Not only that, but Allie points out that they don't know why the professor is so sure the fire was arson. Steeling herself, Cat decides to confront both Naia and Professor Moynihan about their secrets.

Moynihan puts everyone's truth-telling abilities to the test, literally, with a pop quiz experiment that reveals the biggest fibbers in the class. Uncertain how to navigate the treacherous course, members of the class begin forming tentative alliances. But can anyone be trusted in the Liars' Club?

The students show up to class only to discover that they have been invited to a cocktail party at the Professor's house. Their invitations contain secrets— ones that they are not allowed to share with anyone else. Of course, the Party Twins and Alvaro alliance immediately breaks the rules. Once at the house, the Liars Club discovers that their task is to return that secret to its rightful owner, forever binding them together. When Bella and Benedict's cheating is revealed, however, more secrets spill forth.