Jacob becomes obsessed with solving the real-life mystery in his Malty McGuffin book; the mystery is supposed to lead to a real secret treasure. The only problem is that he is being followed by library ninjas intent on getting the book back. Jacob, Buford and Renee use their combined brainpower to decode the clues, solve the riddles, and find the location of the secret treasure... only to be scooped at the last minute by I.M. Greedyguts! Will the library ninjas turn the tables on their principal? Will Jacob return his library book on time?