After a dog she is watching disappears from a city parade and the owner receives a ransom note, thirteen-year-old Sammy must use her detective skills to solve the mystery.

When her history teacher begins receiving death threats and her own name is near the top of the suspect list, eighth-grader Sammy is determined to find the real perpetrator, but she is distracted by her mother's relationship problems, her almost-boyfriend inexplicably avoiding her, and her duties as a reluctant bridesmaid.

Thirteen-year-old Sammy meets a mysterious man who dies of a heart attack after telling her to get rid of the large amount of money he is carrying, leading her to investigate who the man was and how he came to be carrying so much cash.

Junior high detective Sammy Keyes and her friends take a detour through a graveyard on Halloween night and find themselves in the middle of a mystery involving missing people, human skulls, and a ghoulish embalmer, while school presents its own set of tricks and treats.

"Teen sleuth Sammy Keyes solves a classic locked-room mystery aboard a cruise ship"--Provided by publisher.