Returning to Scotland to help Bridget's family repair their ancient castle, the Thea Sisters launch a determined rescue attempt when Bridget is kidnapped, in an adventure marked by mysterious messages, hidden treasures, and Celtic legends.

"Twelve-year-old Addison Cooke just wishes something exciting would happen to him. His aunt and uncle, both world-famous researchers, travel to the ends of the earth searching for hidden treasure, dodging dangerous robbers along the way, while Addison is stuck in school all day. After his uncle unearths the first ancient Incan clue needed to find a vast trove of lost treasure, he is kidnapped by members of a shadowy organization intent on stealing...

Will, now a full-fledged Ranger responsible for a sleepy fief, finds a new adventure as he seeks the traitors who poisoned the king, investigates rumors of sorcery, and tries to rescue his friend Alyss, who is taken hostage.

Superspy middle schoolers Ben and Erica must embark on mission to rescue Erica's grandfather, who was abducted from a remote Alaskan training facility.

The quiet community of Red Rock is upset by an apparent abduction attempt on two middle school girls.

Targeted by Interpol after a series of spectacular heists, a reluctant Amy and Dan are ordered by Vesper One to steal the world's largest diamond, a demand that is challenged by their efforts to rescue the Cahill hostages and stop a Vesper mole.

When Artemis learns that his father has been kidnapped by the Russian mob, he races to the Arctic Circle to make a daring rescue, where he finds an old acquaintance, Captain Holly Short, who is investigating a plot of the goblin mob.

In the aftermath of the 1906 San Francisco earthquake, twelve-year-old Clara finds a baby left on the doorstep of her family's boarding house, and sets out to unravel the surrounding mysteries.

Thirteen-year-old Dan Cahill and his older sister, Amy, thought the search for the thirty-nine clues leading to the source of their family's power was over, but when Cahills are kidnapped by the Vespers, Amy and Dan find themselves with only a few days to fulfill a bizarre ransom request before their friends start dying.

Twelve-year-old Addison Cooke and his friends travel across Asia in an attempt to rescue Addison's aunt and uncle from the clutches of a dangerous gang and prevent the legendary tomb of Ghenghis Khan from falling the in the wrong hands.