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.

A series of burglaries in their quiet community upsets Alex's family, particularly his younger brother Benjie, but the bad guys are no match for the very protective family cat and Benjie's "spy" skills.

When Tom's father is kidnapped and it looks like it was an inside operation by the FBI, Tom vows to test the limits of science in order to find his father.

"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...

Erik Morrissey Ganger and his friend, Sadie Dopple, meet a wealthy recluse while trying to escape tunnels under Isambard Dunstan's School for Wayward children in order to pursue a former foe who has kidnapped Sadie's twin sister.

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.

Hank the Cowdog uses his all of his sleuthing skills as head of ranch security when a major theft occurs on the ranch and Miss Beulah is kidnapped.