Accused of ruining a champion dog's career after an unfortunate incident at a mall show, Luthor is sent to the pound, prompting a skeptical Griffin to hatch a daring plan involving a sinister saboteur, a reclusive trainer, and large supply of red dye.

One day, Mac (smartest boy in his class in a small town in California) receives a telephone call from the Queen of England, recruiting him to find the crown jewels (well, actually just the Coronation Spoon) and so Mac embarks on his first adventure as a secret agent--with the assurance that the Queen will give him a note excusing him from school.

"When rare paintings go missing, the InvestiGators are called on the scene...the ART SCENE! Mango and Brash go undercover and under canvas as internationally renowned painters to expose a crook who has truly mastered the art of CRIME! Can they recover the missing masterpieces and save the city art museum's fundraising gala before it's too late...and they run out of appetizers? Find out in this latest pièce de résistance of action-packed illustrated...

To crack a secret code, Mac follows the clues to France and Japan where he must use his gaming skills and defeat his enemy, the KGB Man.