When her father goes missing, thirteen-year-old Lily Hartman must team up with a clockmaker's son, Robert, and her mechanimal fox, Malkin, to solve the mystery of her father's disappearance and his world-changing invention, a perpetual motion machine called the Cogheart.

"Mister Max, Solutioneer, helps the mayor investigate a string of mysterious fires, while attempting to solve the mystery of his parents' disappearance on the side"--

After thirteen-year-old Tucker Feye's parents disappear, he suspects that the strange disks of shimmering air that he keeps seeing are somehow involved, and when he steps inside of one he is whisked on a time-twisting journey trailed by a shadowy sect of priests and haunted by ghostlike figures.

Ari and his friends are on another adventure in the fifth title in the unauthorized Diary of a Roblox Pro series! Citizens of Blockville have been going missing, and there are rumors that a new threat looms over Ari's town. Ari's best friend Zeke thinks it's zombies. But those don't exist... right?!

The Chicken Squad is on the case when their beloved human, Barbara, goes missing around the same time they hear a report of a headless bear on the loose.

The McNallys are visiting Michigan's Mackinac Island. Gavin and his brother, Gus, take a nature walk. After the walk, Gavin wants to hunt for treasure at a nearby fort. So when Gus goes missing, Gavin is annoyed. But he soon comes to realize what hunting for treasure really means--Page [4] cover.

Eleven-year-old Tilly Pages, who has found comfort in her grandparents' bookshop since her mother's disappearance, now learns that she can bookwander into any story, and decides to seek her mother.

"A fourth action-filled puzzler for teen Sherlock as he plunges into a fight for his life and battles to discover what has happened to his missing friends"--

Cordelia Clay loves the work she and her father do together: saving and healing the remarkable creatures around Boston at the end of the nineteenth century. Their home on Cedar Street is full to the brim with dragons, squelches, and diggles, and Cordelia loves every one of them. But their work must be kept a secret, others aren't welcoming to outsiders and immigrants, so what would the people of Boston do to the creatures they call 'monsters'? One...