The Mystery of the Flying Express

The Hardy Boys Secret Files Collection Books 1-5

Danger Overseas (Nancy Drew: Girl Detective and Hardy Boys: Undercover Brothers Super Mystery #2)

The Gross Ghost Mystery (Frank and Joe Hardy: The Clues Brothers #1)

The Scarlet Slipper Mystery

The Mystery of the Queens Jewels

The Mystery of the Singing Serpent

Katie Fry, Private Eye #1: The Lost Kitten

The Hardy Boys

The Hardy Boys solve a mystery involving the theft of a priceless ancient artifact. With fast-paced action and suspense, the boys must navigate a series of complicated clues and dangerous situations to find the truth.

Discover Your Child's Next Read

The Mystery of the Flying Express

Franklin W. Dixon, 1941

The Hardy Boys Secret Files Collection Books 1-5

Franklin W. Dixon, Scott Burroughs, 2014

Danger Overseas (Nancy Drew: Girl Detective and Hardy Boys: Undercover Brothers Super Mystery #2)

Franklin W. Dixon, Carolyn Keene, 2008

The Gross Ghost Mystery (Frank and Joe Hardy: The Clues Brothers #1)

Franklin W. Dixon, 1997

The Scarlet Slipper Mystery

Carolyn Keene, 1954

The Mystery of the Queens Jewels

Gertrude Warner, Gertrude Chandler Warner, 1998

The Mystery of the Singing Serpent

Ed Vebell, M. V. Carey, Mary Carey, 1972

Katie Fry, Private Eye #1: The Lost Kitten

Vanessa Brantley-Newton, Katherine Cox, 2015