Melody Bird has discovered an abandoned old building in the corner of the graveyard...

Though it's dark and creepy, she can't resist its pull. When she goes to explore, she finds a mysterious boy hiding out there. Hal tells Melody that he's a spy, using the house as a base for his undercover surveillance of a nearby suspected criminal. He's very secretive about the details, but Melody comes to trust him and starts helping him with his mission.

Melody is determined to decode the strange riddles Hal finds hidden in the graveyard, but her friends Matthew and Jake question Hal's story. They decide to turn the tables and find out the truth about him, uncovering the biggest mystery of all...

This extraordinary novel set in the world of The Goldfish Boy is a page-turning mystery with a sensitive story about friendship and trust at its core.