The Mystery of the Monster Mountain
M. V. Carey
The Mystery of the Scar-faced Beggar
The Mystery of the Magic Circle
The Mystery of the Singing Serpent
The Mystery of Sinister Scarecrow
The Mystery of the Blazing Cliffs
The Mystery of Wandering Caveman
The Mystery of the Death Trap Mine
The Mystery of the Rogues' Reunion
Marc Brandel
The Mystery of the Kidnapped Whale
Fiendish Deeds
P. J. Bracegirdle
Five on a treasure island
Enid Blyton
The Circus of Adventure
Five go off to camp
Five go adventuring again
Five Get Into Trouble
The Mystery of the Fiery Eye
Robert Arthur
The Mystery of the Vanishing Treasure
The Secret of the Terror Castle
The Mystery of the Silver Spider
The Mystery of the Green Ghost
The Mystery of the Screaming Clock
The Mystery of the Talking Skull
The Mystery of the Stuttering Parrot
The Mystery of the Whispering Mummy
The Secret of Skeleton Island
The Mystery of the Deadly Double
William Arden
The Mystery of the Purple Pirate
The Mystery of the Shrinking House
The Mystery of the Moaning Cave
The Mystery of the Headless Horse
The Mystery of the Laughing Shadow
The Mystery of the Dead Man's Riddle
The Secret of Phantom Lake
The Secret of the Crooked Cat
The Mystery of the Dancing Devil