It's the night that all the sixth-graders at Hamilton Middle School have been waiting for: the annual overnight field trip to the local science museum and planetarium. Best friends Nate and Connor come bearing treats and, unknowingly, tricks in the form of a spooky old book called Tales from the Scaremaster.

When Nate and Connor crack open the candy to share with their friends, they also crack open the book, and are shocked to find that it writes back. Pretty soon, creepy things start happening at the museum--ghostly sightings, possessed dioramas that the kids swear are moving, and scary noises and movements at every turn. Weirder still, it seems that the mysterious book might be pulling the strings. Can Nate, Connor, Emily, and Bella uncover the mysteries of the book and the haunted museum--or will they end up its latest victims?