This is a sequel to Memories of Shadows. The Man in the Moon becomes livid with the Guardians when they once again see Pitch as a threat and try to keep Jack away from him. So MIM decides that it's time he takes matters into his own hands to get the Guardians to understand that Pitch is no longer a threat.
After 300 years with no memories of her past and a strong desire to be with the Nightmare King, Jack is approached by the Guardians asking for help to stop Pitch, the young spirit agrees only to regain her lost memories and to find out why she is drawn to The Boogeyman. there will be references to the book series.