Sasspants, the mystery-loving guinea pig, returns to solve a new case with her faithful—perhaps too faithful—sidekick, Hamisher the hamster. Lovable-but-clueless pet-shop owner Mr. Venezi posts a help-wanted sign in the hopes he can find someone who will fix his mixed-up cage labels. The residents of Pets & Stuff are worried that too much help might hasten their being sold to different homes. Sasspants and Hamisher fix the signs themselves to forestall any new hire, but someone keeps defacing them. Prime suspects are the new, peppy ferrets, but Hamisher has learned from his mystery reading that the culprit is never the most obvious suspect. When Hamisher’s sleep-deprived sleepwalking (he’s trying not to be nocturnal) makes him suspect himself, Sasspants must recruit a new assistant and step up her furry investigations to find the vandal and clear Hamisher’s name. It’s another lighthearted caper, with much of the humor in the details; in addition to the evergreen mislabeled-cages gag, here Hamisher takes the drastic step of imprisoning himself in a hamster ball. Yue’s adorable, expressive cartoon creatures ably extend Venable's humor. Aftermatter on ferrets and mystery-story vocabulary is instructive and funny. A winning graphic story all around. (Graphic mystery. 6-12)