Bill and Megan Stine have written numerous books for young readers, including titles in these series: The Cranberry Cousins; Wizards, Warriors, and You; The Three Investigators; Indiana Jones; G.I. Joe; and Jem. They live on New York City's Upper West Side with their seven-year-old son, Cody, who believes in ghosts.

When Ricky Reyes dares Jeffrey to get a bloody dagger out of the old McGyver house on Halloween night, Jeffrey is counting on Max, his ghostly friend, to help him.