Henry Carter Hull

The Thea sisters learn about a mysterious shipwreck off Whale Island from their history professor, who disappears, prompting the sisters to search for him and the legendary treasure they think he was searching for before he disappeared.

Fourth-graders Drake Doyle and Nell Fossey combine their detective and scientific investigation skills to solve cases involving a crooked carnival barker, a mysterious ghost, an alien plant species invading wildlife habitats, and a wobbly bridge.

Fourth-graders Drake Doyle and Nell Fossey combine their detective and scientific investigation skills to solve a variety of cases, involving a noisy garbage can, endangered frogs, a stuck truck, and a mysterious love letter.

Thea's friends the Thea Sisters travel to India where they investigate when the monkeys living in the city start stealing jewels.

Nancy thought she had caught the person who was trying to sabotage her model friend Sydney's wedding to Vic, a reality television star, but things are still not running smoothly and Nancy begins to think Sydney may be the problem.

Nancy finds herself in danger when she tries to solve the mystery of an old inn which seems to be jinxed.

When Mr. Hardy disappears while investigating a mystery surrounding a vacant house rumored to be either haunted or an abode for criminals, Joe and Frank search for the truth.

Jared Jensen and his fellow zombie hunters think there is a werewolf loose in the cemeteries of Marshfield, but is it connected with the strange boy called Rudy or not?

Soon after arriving at the Winchesterfield-Downsfordvale Academy for Proper Young Ladies, resourceful seven-and-one-quarter-year-old Alice-Miranda finds her new boarding school to be a very curious establishment with no flowers in the gardens, a headmistress that has not been seen for years, and a mysterious stranger that seems to be hiding out on the premises.