Frank and Joe solve the mystery of the secret locked room in the spooky Dalrymple Mansion.

"What Happened At Midnight" is an exciting mystery novel by Franklin W. Dixon. The story revolves around the adventures of the Hardy Boys, Frank and Joe, who are skilled amateur detectives always eager to take on challenging cases. The plot begins with the Hardy Boys receiving a mysterious message requesting their assistance in solving a perplexing and dangerous case. Intrigued, they set out to unravel the enigma and uncover the truth behind the strange events that occurred at midnight. As the brothers delve deeper into the investigation, they encounter a series of thrilling escapades and encounters with suspicious characters. From hidden passages to cryptic clues, the Hardy Boys use their intelligence, bravery, and quick thinking to navigate the twists and turns of the case. As the story unfolds, the brothers find themselves entangled in a complex web of deception and danger. They must rely on their detective skills and work together to decipher codes, follow leads, and uncover hidden secrets. Throughout their quest for the truth, the Hardy Boys face various challenges, including narrow escapes, daring rescues, and unexpected revelations. With every clue they uncover, the mystery deepens, and the stakes become higher. In their relentless pursuit of justice, Frank and Joe race against time to solve the puzzle before the clock strikes midnight once again. The climax of the story is filled with suspense and excitement, as the Hardy Boys finally uncover the truth behind the mysterious events that took place in the dead of night. "What Happened At Midnight" is a thrilling and engaging mystery that keeps readers on the edge of their seats from start to finish, showcasing the bravery and resourcefulness of the Hardy Boys as they solve yet another intriguing case.

A plot to steal a top-secret instrument vital to the United States space program poses a challenging case for Frank and Joe Hardy. After rescuing a South American stowaway who mutters a warning about “Footprints “ and then vanishes, Frank and Joe discover that documents belonging to their famous detective father are missing and that footprints linger under a window. The young detective’s search for the diabolical mastermind of the “Footprints” spy ring takes them on a flight to a group of islands off the coast of South America.

The Hardy Boys series, first published in 1927, has sold more than 70 million copies! Now with a brand-new look, this is an edition that collectors won't want to miss! In The Mystery of Cabin Island, the eighth book in the incredibly popular, long-running series, Frank and Joe Hardy encounter several dangerous setbacks as they search for Johnny Jefferson and some antique stolen medals. A special treat for Hardy Boys fans and any reader who's new to the series!

To their friends’ envy, Biff and Chet plan to take a boating vacation up the coast. The joy of sending them off soon turns to anxiety as neither of them make contact with home for several days. Convinced that something’s happened to them, the Hardy boys and their friends go on a search filled with adventure and peril in hopes of retrieving their missing chums. This is the fourth book of the Hardy boys series, first published in 1928. While the author is credited to be Franklin W. Dixon, in reality, Leslie MacFarlane and Edward Stratemeyer are primarily responsible for the early volumes, including this one. This Standard Ebooks edition is based on the original 1928 text. This book is part of the Standard Ebooks project, which produces free public domain ebooks.

Frank and Joe find themselves on an uninhabited Caribbean island when they follow clues left by a gang of platinum thieves

Difficult assignments are nothing new to the Hardy boys and this one that takes them to the Deep South is particularly challenging. Their mission: to vindicate a long-dead Confederate general, disgraced during the Civil War because he was accused of stealing hidden gold belonging to a bank. Skillfully avoiding booby traps and flying bullets, the boys persevere in their perilous quest. The arduous search is full of surprises that will thrill all fans of the Hardy boys.

Frank and Joe set out to solve another exciting mystery.

A banker who has been receiving threatening notes enlists the help of the Hardy boys. Before long, the young sleuths find themselves entangled in the investigation of a notorious band of thieves.