In this sequel to A Study in Secrets that's Only Murders in the Building meets The Westing Game, Meg must figure out the identity of the mysterious Mastermind to save her school and her friends.

After winning a scavenger hunt with her new friends--Tana, Zane, and Ryan--Meg Mizuno is looking forward to winter break and enjoying their grand prize of an all-expenses paid trip to California. But after learning that their boarding school, Leland Chase Academy (called Last Chance Academy by students), is in danger of shutting down, it's hard to enjoy the sun and surf.

When they return, the Head of School reminds the student body of their mandatory participation in the Student Showcase, with the goal of bringing in needed funds to the school. If that weren't enough pressure, Meg discovers a new note: the Mastermind wants her to help him with one more scavenger hunt. This time, though, she must work alone, or else the Mastermind will not only ruin the school, but also publicly reveal secrets about all her friends that would turn their lives upside down.