舒克与贝塔得知鼠王老家被人类破坏，救援时遇神秘机器人，追踪发现疯狂老鼠的实验室及能量晶石。能量波让两人异变，成为微缩世界的“人形老鼠”。寻源途中遇思诺，从冲突到信任，揭开真相后联手摧毁信号天线，阻止灾难，为人与动物共处点燃希望。Shuke and Beta learn the Rat King’s hometown is destroyed by humans. Rescuing it, they meet a robot, find the Mad Rat’s laboratory and energy crystal. The wave mutates them into "humanoid mice" in a miniature world. They meet Sinuo, build trust, uncover the truth, and jointly destroy the antenna to stop disaster, igniting hope for coexistence.