- Author: Carolyn Keene
- Binding: PB
Deidre Shannon is turning eight years old. So naturally, she'll be having a Super Sweet Half-Sixteen birthday party this year! The theme? Mermaids. Nancy Drew and friends are invited to the big bash, where all guests must wear under-the-sea-themed costumes. When someone sabotages the fun with a squirmy snake in the pool, the girl sleuth and her pals set out to find the culprit. The first in an interactive Nancy Drew chapter book series, includes space for readers to jot down ideas and help solve the mystery.