Gretta refuses to attend the Woodside High Sweetheart's Dance for fear of it being ruined like her coming-of-age ball. Meanwhile, Baldric dives headfirst into party planning with the students of Woodside. But on the eve of the dance, an angry ghost with a grudge against Gretta makes its presence known.

Sightings of a large creature in Woodside Lake rouse the suspicions of Zack, the school newspaper editor. Dwight and Gretta are recruited to help, only to find out that the creature is Winnie the Wyvern with an urgent message for Dwight.