Secrets of the Lone Wolf

Michael Lanyard, the reformed jewel thief known as the "Lone Wolf," is giving a speech at a society function when a woman delivers an urgent message, asking him to meet her at the Burton Hotel later that night. Before Lanyard's valet, Jamison, is able to convey the message, Sergeant Dickens of the police department appears, handcuffs Lanyard and takes him to the docks to meet Inspector Crane. At the docks, Crane apologizes for the handcuffs and asks Lanyard to help protect the Napoleon jewels, which several French refugees have smuggled from Europe to sell them for profits with which to fight the Germans. As Bob Garth, the private detective hired to safeguard the gems, opens the safe, Paul Benoit, posing as a customs agent, sneaks onboard the ship and is caught by Helene de Leon, the model hired to display the jewels. Sensing that something is amiss, Lanyard warns Crane not to trust Helene or Paul. Meanwhile, Jamison, despairing that Lanyard will not be able to keep his appointment with the damsel in distress, goes to the Burton Hotel and is confronted by a roomful of jewel thieves who mistake him for the Lone Wolf. Among the thieves are the ship's steward, Dapper Dan Streever, and Bubbles Deegan. When the crooks refuse to believe Jamison's protests that he is only a butler and insist that he steal the jewels, Jamison calls his employer for help, and Lanyard advises him to tell his captors that he must return to the apartment to retrieve his tools. Bubbles escorts Jamison to the apartment, but when Dickens pounds on the door, she flees out the back, and Jamison and Lanyard realize that the gang will now try to steal the gems themselves. Leaving Dickens to soak his weary feet in a beer bath, they hurry to the docks to prevent the theft, but the police refuse to grant them admittance to the ship. Meanwhile, onboard, Colonel Costals, one of the refugees, nervously awaits the arrival of a jewel buyer from Chicago. When the buyer appears, the steward knocks him unconscious and Streever takes his place. Upon discovering the unconscious man's body, Dickens, who has donned his socks and shoes and hurried to the docks, blames Lanyard and handcuffs him to the deck, but Lanyard soon slips out. As Garth prepares to remove the jewels from the safe, the lights go out and the fire alarm sounds. By the time the lights are switched back on, Garth is found beaten unconscious and the jewels are missing. Later, after Garth dies, Lanyard is charged with his murder and realizes that he must find the real thieves to clear his name. When Jamison recalls seeing Streever among the jewel buyers and recognizes the steward as one of the gang members, Lanyard instructs him to locate the thieves. Lanyard agrees to sign a confession if the police free Jamison, but after being released Jamison is taken prison by the gang. Escaping from the police once again, Lanyard returns to his apartment, and soon after, Helene appears and asks if Paul was involved in the robbery. When Helene mentions that Jamison has been kidnapped, Lanyard sets out to rescue his butler. Meanwhile, at the hotel, the gang notices Lanyard's photograph in the newspaper and finally realizes that Jamison is not the notorious Lone Wolf. When they discover Dickens' badge in Jamison's pocket, they decide to kill him just as Lanyard sneaks into their hotel room and introduces himself. After pulling out a gun, Lanyard unties Jamison, and they return to the docks and sneak onboard the ship. While searching for a clue to the theft, Lanyard finds a thread tied to the ship's rail. Later, Crane climbs on deck to arrest Lanyard and trips over a cord. When he tugs at the cord, a bag containing hardware emerges from the water below and Lanyard explains that the bag contained the jewels which he replaced with the hardware, hoping to ensnare the thief. Continuing that he stashed the jewels in the colonel's pockets, Lanyard proposes re-enacting the crime to trap the criminal. Crane consents, and as the lights are extinguished, Streever, hiding under a canvas tarp, emerges and steals the gems from the colonel's pockets. After Streever is apprehended by the police who are waiting on the dock, Lanyard is exonerated and introduces Paul as a former French military officer who has been working undercover for his country's freedom.