Jasper is thrilled when he finds his dad�s favorite childhood toy, Marcel Mouse, at his grandmother�s place. He�s so afraid to lose the family treasure that he keeps Marcel on a string around his neck. But sometimes Jasper has to take off the little plastic mouse, and that leads to all sorts of trouble. First, Marcel goes missing from under Jasper�s pillow, then he gets sent to the principal�s office and disappears again! Then one day, something TERRIBLE happens, and it seems Marcel might be lost forever ó Will Jasper ever see Marcel Mouse again?