Agent Nine and the Jewel Mystery: A Story of Thrilling Exploits of the "G" Men

In Short

Graham M. Dean’s 1935 juvenile mystery follows newly minted Federal Bureau of Investigation agent Bob Houston, designated Special Agent Nine, as he takes on a high-stakes diamond-smuggling case. Assigned to work alongside his antagonistic departmental rival, Tully, Bob faces sabotage, mysterious disappearances, and physical attacks aboard the Southern Limited heading into Florida. When his mentor, veteran detective Merritt Hughes, goes missing in Jacksonville, Bob navigates coastal swamps alongside a local sheriff to locate a secret base on Lost Island. It endures as an authentic piece of mid-century American law-enforcement fiction for young readers.

The Story

Freshly sworn into the Federal Bureau of Investigation, young Bob Houston steps out of the Department of Justice Building alongside his uncle, Merritt Hughes, an esteemed department detective. Bob’s enthusiasm is tested immediately when bureau chief Waldo Edgar reprimands Bob’s colleague and rival, Tully, for leaking news of a past raid to the press. To channel their fierce competitive drive, Edgar assigns both young agents to solve a persistent diamond-smuggling operation baffling customs officials along the southern coast. Bob offers an olive branch, but Tully rejects any cooperative effort, vowing to beat Bob to the solution within two months.

Boarding the Southern Limited for Florida, the agents find the journey fraught with danger and bizarre occurrences. Tully suffers a sudden, debilitating spell of illness in the smoking compartment, during which his confidential report on the smuggling ring vanishes. Suspicious behavior from fellow passenger Joe Hamsa—a traveling diamond salesman who abruptly disappears from the moving train during a torrential storm—heightens Bob’s vigilance. Late at night, an unseen attacker douses the lights in the observation car, blinding Bob with a flashlight and knocking him unconscious. Upon waking, Bob discovers that Tully has vanished entirely from his berth. Shortly thereafter, an intruder creeps through the dark car. Bob confronts Hamsa in the aisle, leading to a violent struggle that tumbles both men off the train onto a narrow railroad trestle over rushing waters. Hamsa mockingly evades immediate arrest by plunging off the slippery bridge into the storm.

Reaching Jacksonville, Bob drafts an extensive report for headquarters and searches for his uncle Merritt, who had been dispatched earlier to investigate coastal leads. When Merritt fails to return to their hotel after venturing toward the waterfront, chief Edgar orders Bob to push further south to Atalissa, leaving agent Condon Adams to search for the missing detective. In Jacksonville, Bob survives an armed ambush by gun-toting gangsters, subduing them alongside Adams in a quick-draw firefight before boarding a local accommodation train bound for the coast.

Arriving in Ainsworth and then Atalissa, Bob teams up with Sheriff McCurdy, a pragmatic lawman suffering from cold-weather rheumatism. Learning from a local barber about suspicious night flights and a speedboat streaking toward Lost Island, Bob and McCurdy commandeer a boat to investigate the swampy hideout. Disabling their craft’s motor to prevent theft, they wade through cold, clammy marshland under cover of darkness, drawn toward a lighted torch mounted on a tall pole. Bob discovers an amphibian aircraft used to transport illicit gems, along with a ramshackle bayou shanty. Inside, they find the missing Merritt Hughes held captive alongside the smuggling ring’s ringleaders. Bob and McCurdy overpower the guards, free Merritt, and confiscate a leather case filled with uncut diamonds. Setting fire to the shanty to eliminate the criminal den, Bob, his uncle, and the sheriff ferry their captives back to town, bringing the bureau’s hard-fought case to a triumphant close.

How It Unfolds

A tense assignment Bob Houston receives his first major case from bureau chief Waldo Edgar, who pairing him with his bitter departmental rival, Tully. Refusing Bob’s offer of a truce, Tully vows to solve the coastal diamond-smuggling mystery alone within two months.

Peril on the Southern Limited En route to Florida aboard a storm-battered train, Tully collapses from a sudden illness, allowing his confidential case files to vanish. A suspicious passenger named Joe Hamsa vanishes, and an unknown assailant knocks Bob unconscious before Tully disappears from his berth.

Showdown on the trestle Bob catches Hamsa prowling the darkened train aisle, leading to a fierce struggle that hurls both men onto a slippery railroad bridge. Mocking the young agent, Hamsa deliberately rolls off the edge of the trestle into the churning waters below.

Trouble in Jacksonville Arriving in Florida, Bob learns his uncle Merritt has disappeared while investigating the waterfront. After surviving a midnight drive-by attack by gangsters, Bob leaves the search for his uncle to agent Condon Adams and presses south toward the coast.

Infiltrating Lost Island Joining forces with Sheriff McCurdy in Atalissa, Bob wades through cold bayou mud toward a hidden island camp marked by a tall signal flare. They discover a concealed amphibian plane used for transporting smuggled gems to a secluded shanty.

Untangling the web Bob and McCurdy breach the shanty, rescue the captive Merritt Hughes, and recover the stolen diamonds. After torching the criminal hideout, the federal agents and sheriff escort their captured prisoners back to civilization.

The People

• Bob Houston (Special Agent Nine): The youngest agent in the Federal Bureau of Investigation, driven by an unwavering sense of duty, tactical sharpness, and quick-draw marksmanship. He seeks to prove himself on his first major case while refusing to compromise his fair-play principles.
• Tully: Bob’s arrogant rival within the bureau. Eager for personal glory and front-page news, he rejects Bob’s offer of partnership, only to fall victim to sudden illness, stolen papers, and a mysterious abduction early in the investigation.
• Merritt Hughes: Bob’s uncle and a veteran detective in the Department of Justice. He acts as Bob’s mentor, offering practical advice on federal service before going missing while investigating the smuggling ring’s southern hideout.
• Joe Hamsa: A ruthless operative posing as a traveling diamond salesman. He steals confidential reports, attacks Bob aboard the Southern Limited, and peddles smuggled European gems across the country.
• Waldo Edgar: The stern chief of the Federal Bureau of Investigation who directs the department's high-stakes cases, demands strict adherence to secrecy rules, and orchestrates the strategy to break the coastal smuggling ring.
• Sheriff McCurdy: The plain-spoken, rustic lawman of Atalissa. Despite his nagging rheumatism and distaste for wading through swamp mud, he provides vital local knowledge and steady backup during the raid on Lost Island.

In Its Own Voice

“Well, Tully, you just run along and do your best; but I’m serving fair warning on you right now that if you try to step on any of my toes, you’ll wish you hadn’t.”

“There was just a chance of success for a desperate play and he took the chance.”

“We’ll have to leave that for another trip,” smiled Merritt Hughes. “Sheriff, let’s start for town.”

What It's Really About

Beneath its fast-paced action, the book explores the professional ethics and discipline required of modern law enforcement. It contrasts Bob’s selfless dedication and commitment to departmental protocol with Tully’s destructive ambition and desire for personal headlines. The narrative emphasizes that institutional success relies on cooperation, fair play, and methodical teamwork rather than solitary bravado or publicity-seeking. Additionally, it highlights the constant physical danger and personal sacrifice implicit in federal service, as agents must routinely risk life and limb in remote, lawless environments to uphold justice and protect national security.

Why Read It Today

This novel offers a crisp, entertaining window into 1930s popular juvenile fiction and the cultural fascination with early FBI "G-Men." Readers who enjoy vintage procedural adventures, classic train mysteries, and straightforward detective fiction will appreciate its swift pacing and nostalgic tone. The story moves cleanly from rain-slicked Pullman cars to murky Florida bayous, maintaining steady tension through constant action, quick-fire gunplay, and clear-cut moral stakes.

The reading experience is light and direct, though modern readers will notice period tropes and simplified character dynamics characteristic of 1930s series books. The prose avoids lengthy exposition, relying instead on concise dialogue, physical confrontations, and traditional detective work. While the plot relies on fortunate coincidences and conventional villainy, the authentic details—such as vintage telegraph messages, steam trains, and early aviation transport—provide a fascinating historical snapshot. It remains a pleasant, quick-moving adventure that captures the heroic idealism of mid-century American crime-busting fiction.