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

The solutions to 10 mysteries solved by Leroy "Encyclopedia" Brown are given in a separate section challenging the reader to match wits with the 10-year-old mastermind of Idaville's war on crime.

Henry, Jessie, Violet, and Benny are "on the air" and on the trail of a mystery, too! The children are helping out at a local station, where they're performing a play live on the radio, just like in the old days, but sometimes the radio station seems haunted.

Ten-year-old Cam, possessor of a photographic memory, and her friend Eric investigate what seems to be a brief appearance of U.F.O.s.

Super-sleuth Herculeah Jones's investigation of the attempted murder of Meat's uncle leads them to a mystery bookstore named Death's Door.

While having a picnic on the docks, animal detectives Bunny and Jack meet a dog whose one and only lawn chair is missing, and they set out to solve the case.

After the new hydrofoil they are guarding is stolen, the Hardy boys face frequent danger in solving a mystery involving criminals who operate by signs of the zodiac.

The Hardy boys try to find out who is sabotaging a musical play about Sherlock Holmes.