After years in foster care, April gets to live in a mansion where she and four other children are caught up in a mystery related to a missing heir, a lost legacy, and the Phantom.

Enola Holmes, much younger sister of detective Sherlock Holmes, must travel to London in disguise to unravel the disappearance of her missing mother.

Alex Cross' son, Ali, is eager to follow in his father's footsteps as a detective, but when his best friend goes missing, what price will he have to pay to solve the mystery? Ali Cross is determined to follow in the footsteps of his father, former detective and FBI agent Alex Cross. When Ali's best friend Gabe goes missing, Ali knows that with every passing day, the less likely Gabe will be found. This is Ali's very first case. If he inherited any...

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.

Thea Stilton and her journalism class try to find a missing student.

After fourteen-year-old Ozzy's scientist parents have been kidnapped, Ozzy's only help may be a classified ad that says, "Wizards for hire."

Discovering his supernatural ability to alter reality, Michael Malone, a boy whose father mysteriously vanished three years earlier, is recruited by an organization dedicated to investigating paranormal phenomena.

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.

While his widowed mother continues to search for him, eleven-year-old Tom, presumed dead after drifting away down a river, finds himself trapped in a series of underground caves with another survivor and a dog, and pursued by murderous treasure-hunters.

Two years after their football player father disappeared, Winston and Louise wrestle with their grief while investigating mysterious teachers, innovative science, and a captive bear.