Word of Mouse (2016) is a middle grade book written by James Patterson and Chris Grabenstein and illustrated by Joe Sutphin. It follows Isaiah, a blue-furred mouse who possesses remarkable talent and intelligence but is easily frightened. After escaping from the mysterious laboratory he once called home, he is forced to navigate the outside world for the first time. As he tries to find a way to rescue his family, he befriends other mice and a lonely girl named Hailey and inspires them to embrace what makes them special.

This guide references the 2016 e-book edition by JIMMY Patterson Books.

Content Warning: This guide references scenes in the book depicting experimentation on animals in a laboratory setting and discusses antisemitism.

Plot Summary

The story follows a blue mouse named Isaiah. It begins as he and his family attempt to escape the laboratory where they are trapped. Isaiah struggles to keep up and ends up alone after being trapped in garbage during the escape. After crawling through a storm drain, he overhears that his family has all been caught by the humans from the lab. He resolves to survive on his own and begins his search for food and safety in a nearby suburban neighborhood.

Isaiah first finds temporary refuge in a trash can but is surrounded by a gang of rats. He uses his intelligence and ability to speak human words to scare them away by shouting. Despite this success, he soon faces a sphynx cat named Lucifer. He escapes into a house, where a woman with a rolling pin attacks him. He hides in a cinder block outside for the night, but feels lonely without his family. The following day, he searches for food, but only finds slop in an otherwise empty trash can. As he reluctantly eats, he hears a beautiful song. Its source is a girl mouse named Mikayla.

While startled by him at first, Mikayla softens when he shares the story of losing his family. She invites him to her home to meet with her mischief, or family. Upon arrival, one elder, James the Wise, welcomes Isaiah and offers him a home until he reunites with his family. Gabriel and Gwindell, two of Mikayla’s relatives, give Isaiah a tour of the burrow. They take Isaiah on several food raids on the house above, which belongs to the Brophy family. Isaiah’s ability to read and keen senses impress the other mice. When Lucifer arrives, Isaiah risks his life to retrieve some fallen doughnut holes.

Isaiah returns to the burrow to a hero’s welcome. Mikayla also thanks him and reveals that her reluctance to sing openly is due to her family’s traditional expectations. This makes Isaiah feel he will never truly belong in the mischief, prompting him to quietly retreat. He turns his attention back to attempting to reunite with his family. While leaving a trail for his family in the neighborhood, he barely escapes a bird attack and hides in another of the houses. Inside, he meets a girl, Hailey, who screams and tries to hit him with a newspaper. He uses the keyboard of the nearby computer to ask her to calm down. Once she does, they talk, bonding over how they are both isolated due to their appearances.

After they talk, Isaiah heads back to the Brophys’ house. Once outside, he is snatched up by a red-tailed hawk, who drops him into its nest. Isaiah startles its chicks with a shout, allowing him to escape back to the house. Back at the burrow, Isaiah volunteers for the next food run. Once in the kitchen, Isaiah hears the familiar jingle of keys from the lab and realizes that Mr. Brophy is one of the men who works there. Isaiah urgently warns Gabriel about Mr. Brophy, but the other mice are distracted by the fast-food bags on the cabinet and floor.

Their excitement ends when Gwindell triggers a mousetrap, which clamps down on her tail and leg. Isaiah instructs the mice to hide Gwindell and the trap behind the refrigerator when Mr. Brophy returns. Despite the other mice thinking there’s no hope, Isaiah plans to use a lever to free Gwindell from the trap. He is later summoned by the Council of Elders and learns they voted to adopt him into the mischief. While reflecting on the family he left behind, Isaiah bumps into Mikayla, who invites him to join her for a moonlight stroll. Their walk is interrupted by the sight of Lucifer attacking the baby hawks. They intervene and draw him away from the chicks. The mother hawk returns, grabbing Lucifer and dropping him onto the driveway. Taking advantage of the distraction, Isaiah leads Mikayla to Hailey’s house. The girl greets the two mice, and they share a midnight snack. Afterward, she gives the mice a ride home in her sweatshirt hood. As they snuggle, Isaiah sings to Mikayla, who sings a beautiful song in return.

While the Brophy family is out, the mice attempt a large-scale food raid. Lucifer attacks them and traps them in the bathroom. Isaiah plans to summon the rest of the mischief by having Mikayla sing the Battle Call of the Mice. Despite skepticism from the others, her singing brings an overwhelming number of mice to their aid, scaring Lucifer away. When Isaiah and Mikayla revisit Hailey’s house and update her on this latest victory, the mention of laboratories causes him to break down and finally share the full story of his past.

Hailey tells Isaiah about the lab where his family is being held. He decides to stage an attack using an army of mice. They gather in Mr. Brophy’s truck, and Isaiah hides in his lunch bag. Once inside the lab, Isaiah hears Mr. Brophy and the head scientist, Dr. Ledbetter, discussing heightened security measures. Upon realizing the original plan won’t work, Isaiah decides to complete the rescue mission alone. He finds his family trapped and two scientists preparing to experiment on his brother Abe. Isaiah distracts them and uses a computer to free his family. They all meet again at the locked door and use teamwork to get it unlocked, and Isaiah calls the army outside to charge the lab. Hailey arrives with the police and exposes the lab’s illegal activities, leading Dr. Ledbetter and Mr. Brophy to be arrested.

Isaiah introduces his siblings to Hailey. She proposes they attend her church’s Animal Blessing ceremony, offering a chance for the mice to be seen in a positive light. Although the congregation is afraid of the mice, Hailey tells them it is important to recognize the value of all creatures. Isaiah and Mikayla sing a song about unity and acceptance, bringing the congregation to tears. The priest, Father Ed, praises Hailey’s message, and the service proceeds. After the ceremony, Abe shares troubling information about another lab with worse conditions. Despite the revelation that the animals experimented on are cats, Isaiah commits to rescuing them, too.