Tyler Bowers and his robot best friend, Rob, are always up for some adventure and detective work-even the semi-dangerous kind! Police Chief Clancy has a new mission for the Undercover Brothers: To stop a horde of ninjas!It is now up to Tyler, Rob, and their martial arts expert friend, Kate, to find where the ninjas are lurking.Only one obstacle will test their strength and bravery.... The Ninja Grandmaster-the most powerful ninja in the world!This story is a funny adventure that is engaging for children, middle school students, and grown-ups too!Check out The Undercover Brothers: Skateboard Spies (Prequel Story) to find out how it all began.