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.

It's a dark and stormy afternoon when Sasspants, PI(G), leaves Mr. Venezi's pet shop to live with a new owner. Soon there's a mystery afoot back at the shop: the cat from the bookstore next door has disappeared. All the pet shop animals are putting on their detective hats, but their fluffy-but-faraway guinea pig detective can't help them follow the clues! Can Hamisher the hamster solve this cat-napping without Sasspants? He's going to try his furry...