The Secret Serum
While the gang grows more divided, a vampire is stealing seemingly random items from around Crystal Cove. Velma and Daphne investigate separately, suspecting Nan Blake, while the Fred, Shaggy, and Scooby investigate the botanical gardens. The gang reunites when the vampire steals an orchid. They visit the Dinkley library, where Ed secretly helps Daphne discovers a joke youth serum requiring all the ingredients that have so far been stolen. They fail to capture the vampire when they try to trap her in a restaurant’s wine cellar, but successfully capture her in a museum. She’s revealed to be Nan’s assistant, Sheila Altoonian, who is jealous of Nan’s looks. Despite the success, the gang is still split, with Velma suggesting “maybe we’re not a team anymore”.