Hopper's Destiny
March 2015

Book 3
Coming Soon!

Hopper is just an ordinary pet-shop mouse—until he escapes. Soon he finds himself below the bustling streets of Brooklyn, deep within the untamed tangles of transit tunnels, and in Atlantia, a glorious utopian rat civilization.

But all is not as it seems. Hopper misses Pinkie and Pup, the siblings he lost in the escape attempt. Atlantia is constantly threatened by roving rebels who wish to bring the city to its knees. And there are cats everywhere, cats who would normally eat a rodent in a second, but leave the rats unharmed . . . and no one can seem to answer why.

Soon Hopper is caught in the crosshairs of an epic battle, one that spans generations and species. As the clashes rage, Hopper learns terrible, extraordinary secrets.

Deadly secrets about Atlantia. Painful secrets about his friends. And one powerful secret about himself.






Meet the Author and Illustrator

LISA FIEDLER is the author of several novels for children and young adults. She divides her time between Connecticut and the Rhode Island seashore, where she lives happily with her very patient husband, her brilliant and beloved daughter, and their two incredibly spoiled golden retrievers.

VIVIENNE TO has illustrated several books, including the Underland Chronicles series by Suzanne Collins and the Randi Rhodes, Ninja Detective series by Octavia Spencer. As a child, she had two pet mice escape. She currently lives in Sydney, Australia, with her partner and her ginger cat. Visit her online at vivienneto.com.

Lisa Fiedler on Tour!

Lisa Fiedler and Mouseheart might be on their way to a bookstore near you! Check the tour dates below for a list of the places where you can meet her.

Explore the World of Mouseheart!

Travel below the streets to discover the world Hopper finds deep beneath the heart of Brooklyn.


Living safely tucked away in pet stores and the homes of humans, Uplander animals live pretty peaceful lives—though they might never see farther than the walls of their cages. Most of them will never know that there’s another world entirely just beneath their feet.

The Rebels

Led by the notorious Firren, the rebels live on the fringes of both rat and mouse society, answering to no one. If nothing else, they can at least be called courageous—they’re not afraid to stand openly against Emperor Titus, or to face life in the tunnels without Atlantia’s protection.

The Müs

Feared by some and pitied by others, the Müs have a long and much disputed history. Some say they are cruel and fearsome, while others say they deserve the protection of Emperor Titus and the rats of Atlantia. All anyone can say for sure is that the Müs haven’t ruled the tunnels around Atlantic Center in years.

The Ferals

Feral cats were once the undisputed rulers of the tunnels beneath Atlantic Center. Now, under the leadership of Queen Felina, they live in harmony with the rats of Atlantia, but no one seems to be sure why—or certain that it will last.

The Romanus

Hailing from the glorious rat city of Atlantia, the Romanus live in luxury under the protection of Emperor Titus. The city’s walls keep them safe from the dangers that abound in the tunnels beneath Brooklyn, but who knows what other secrets they hide...

Meet the Characters


Though small in size, there’s no questioning the enormity of Hopper’s courage. His true destiny is revealed when he escapes from his pet shop cage and finds himself in the dark tangles of the Brooklyn subway system. Perhaps a tad naïve at first, he soon develops the heart of a true warrior.


Hopper’s sister, Pinkie, is fierce and bullish—maybe even a bit of a bully. You can call her mean, nasty, stubborn, vicious; that’s fine. But never question her loyalty.


Pup is Hopper’s brother. He may be a runt and he may be scared of the world outside, but if one thing is true, it’s that he believes the best about and sees the goodness in everyone—even those with nefarious intentions and questionable moral character.


Zucker is prince of the Romanus, a tribe of rats who live in Atlantia. Though he is of royal blood, Zucker isn’t too happy about the responsibility. Still, he hopes to leverage his privilege to make Atlantia a better place for all tunnel-dwellers. He only wishes his best-friend, Dodger of the Müs tribe, was still alive to help see this vision come to pass.

Emperor Titus

Fierce and formidable, Titus is the Emperor of Atlantia and its outlying colonies. His closeness with the feral cat queen is sometimes questioned, but never challenged. After all, it is Titus who founded Atlantia and it is Titus who keeps his rats—and the refugee rodents he takes in—safe from the perils of the metal monsters (we’d call them trains), the savage Müs, and the roving rebels of the transit tunnels.


Two words describe Felina, queen of the feral cats: gorgeous and cruel. Her long, luscious white hair is always perfectly coiffed, even after striking a deadly blow. She rules with an iron claw.


Don’t mistake Firren’s petite stature for weakness. The leader of the rebel ranger rats is anything but weak. She’ll just as soon run you through with a sword as she will blink.

Educator Resources

Mouseheart - Common Core Curriculum Guide

Bring all the adventure of the Mouseheart series into your classroom with this downloadable curriculum guide featuring Common Core aligned discussion questions and activities for English Language Arts.