Nick and his friend Marta decide to investigate when a mysterious fire starts near a Florida wildlife preserve and an unpopular teacher goes missing.

"Twelve-year-old twins Bickford and Rebecca Kidd and their two older siblings travel to Africa to track down priceless artifacts that will keep the family's treasure hunting business afloat long enough to rescue their kidnapped mother--and possibly find their missing father"--

When the evil Overtakers gain control of a computer server at the Magic Kingdom, allowing them to put the holographic hosts into permanent comas if they should fall asleep, Finn and the others race against time to foil the plan.

Reynie, Kate, Sticky, and Constance, all graduates of the Learning Institute for the Very Enlightened and members of the Benedict Society, embark on a scavenger hunt that turns into a desperate search for the missing Mr. Benedict.

"The Hardy Boys are determined to find their friend when she vanishes into thin air."--

"When Enola Holmes, sister to the detective Sherlock Holmes, discovers her mother has disappeared, she quickly embarks on a journey to London in search of her. But nothing can prepare her for what awaits. Because when she arrives, she finds herself involved in the kidnapping of a young marquess, fleeing murderous villains, and trying to elude her shrewd older brothers - all while attempting to piece together clues to her mother's strange disappearance....

While attending an amusement park under the new ownership of their friend Daisy, Joe and Frank investigate the disappearance of a patron who was last seen riding a hit attraction, an event that has threatened Daisy's family's livelihood.

Twelve-year-old Alice Jones and her family visit Aviles Island, where her mother disappeared long ago, and forms an unlikely friendship with Leo Mercury, who also wants to use the island's special power to contact a lost loved one.

When Kirsten's neighbor and friend, Erik Sandahl, disappears, everyone believes he is skipping out on the money he owes Uncle Olav, but Kirsten believes that something is terribly wrong and sets out to clear her friend's good name.

"The Kidd children--including twelve-year-old twins Rebecca and Bickford--follow mysterious clues that take them from China to Germany, in the hopes of finding their missing father and the treasure that will finally free their kidnapped mother"--