Detective Izzie takes the case of Mateo's missing comic book; Nova, the head of the Insomniacs, probes into a mystery of her own.

The hunt for the Sandman, the only one who can repair Lunia's hourglass, brings the kids to the dangerous Murky Realm.

Determined to give the Insomniacs a night of good dreams, Izzie and friends bring them to the Candy Realm. However, no place is safe from the Nightmare King.