Masterpieces of Mystery in Four VolumesMasterpieces of MysteryReading editionChapter navigation14 reading sectionsGo to chapterChoose a chapter…Masterpieces of MysteryRIDDLE STORIESNOTEFOREWORDMASTERPIECES OF MYSTERYTHE MYSTERIOUS CARDTHE GREAT VALDEZ SAPPHIRETHE OBLONG BOXTHE BIRTH-MARKA TERRIBLY STRANGE BEDTHE TORTURE BY HOPETHE BOX WITH THE IRON CLAMPSMY FASCINATING FRIENDTHE LOST ROOMBeginning of this editionNext chapter →RIDDLE STORIESAll chapters and sections (14)Masterpieces of MysteryRIDDLE STORIESNOTEFOREWORDMASTERPIECES OF MYSTERYTHE MYSTERIOUS CARDTHE GREAT VALDEZ SAPPHIRETHE OBLONG BOXTHE BIRTH-MARKA TERRIBLY STRANGE BEDTHE TORTURE BY HOPETHE BOX WITH THE IRON CLAMPSMY FASCINATING FRIENDTHE LOST ROOMIn Four VolumesRIDDLE STORIES →