Velma finds a mysterious ancient scroll while trapped by a harpie in an ancient building, which highlights the escape route. In order to escape, the gang has to decode the old Grecian messages, which results in a flashback to the gang’s counterparts from Greece. It seems the ancient Grecian gang has to solve the mystery of a legendary spider monster named Arachne whom is terrorizing their village. This thousand-year-old plot eventually leads to the present-day gang formulating a plan to escape from the evil harpie.
