While shopping at an ice cream store in the desert, robbers attempt to steal an ATM. Ben and Grandpa Max capture the villains, but this is only the lesser of their problems. Then they drive to a retirement center to visit Aunt Vera for the weekend, but something very strange is happening here. Ben finds out that there is an evil species of alien shape-shifters taking over the retirement center for food. How will Ben save the day from robbers, strange aliens, and cheek-pinching aunts?