You probably know that Leonardo da Vinci painted the Mona Lisa. Did you know that he also invented an early version of a helicopter and a tank, and that he planned to execute the Time Warp Trio for spying on his inventions? Sam's bright idea to look for the inventor of the Book takes the guys to 15th century Italy to meet up with Leonardo. But it's going to take at least three more bright ideas, two magic tricks, and one great invention to get them out of trouble and safely back home. If not, it could be a lifetime of Italian army toilet-cleaning detail for Joe, Sam, and Fred.
"Nonstop action and lots of laughs" (School Library Journal).