Hopper lives in a Brooklyn pet shop with his sister Pinkie and little brother Pup. All he’s ever known is the inside of the pet shop until the day the boy with the snake comes. The boy’s snake is hungry and when the pet shop keeper comes for them, Hopper realizes they are feeder mice, ready to be fed to the boy’s snake! He quickly hatches a plan with his sister to escape their cage and in all the commotion they lose sight of Pup, who was tossed to the ground during their daring escape. Soon, even Hopper and Pinkie are separated and Hopper finds himself in an underground tunnel. He feels hopeless and alone until he meets Dodger, a rat prince from the city of Atlantia. Hopper’s awe at this magnificent place overwhelms him; he settles in and believes he’s made it home. Unfortunately, Atlantia harbours a dirty secret with its’ refugee camps and it is Hopper’s destiny to liberate the inhabitants after the truth is revealed.While there was some violence, I’ve read Brian Jacque’s Redwall and find Mouseheart to be less gruesome. Swords and other armory do make an appearance to enhance the plot scenes.