When guinea pig Sasspants leaves Mr. Venezi's pet shop to live with Detective Pickles, and hamster-detective Hamisher retires, the other animals must try to solve the case of the missing bookstore cat must be solved without their help.
Guinea pig Sasspants knows something is wrong with ninth-grader Viola, the new pet shop assistant, so when Mr. Venezi goes missing Sasspants and Hamisher put their private investigation skills to the test.
Sasspants, the reluctant guinea pig private investigator, is drawn into another mystery by Hamisher the hamster who believes there is a ghost in the pet shop.
Sasspants, a guinea pig, reluctantly agrees to act as a private investigator when Hamisher the hamster begs for her help in discovering who is stealing sandwiches from the pet shop's befuddled owner.
Enthusiastic sidekick Hamisher the hamster and reluctant detective Sasspants the guinea pig investigate when their beloved home--Mr. Venezi's pet shop--is vandalized.
