Sam Waters is desperate to have a pet. But his parents say that first, Sam must prove he's responsible. So he takes an after-school job in a pet store called Little Shop of Hamsters. To his horror, Sam soon finds that cute, little hamsters can become very UNCUTE monsters. Suddenly, Sam isn't fighting for a pet--he's fighting to survive! Could the souvenir he got in HorrorLand have anything to do with this?

Each eerie adventure of the next seven-book arc begins with a trip to the Chiller House, a gift shop only found in HorrorLand. Kids are invited to take a little horror home with them and given a souvenir and a miniature Horror. At home, the kids experience wild things with their "free" gift, while the glowing, menacing Horror keeps an eye on the fun. When it's time for their payment, the Horror takes them back to shopkeeper Jonathan Chiller.