The Lone Wolf Strikes 1940

Wealthy banker Phillip Jordan, Roy Gordon, is taken in by Binnie Weldon, a younger woman. He graciously offers her the use of a very valuable pearl necklace for her birthday celebration. She has no trouble swapping it for a good imitation and giving the real one to her boyfriend, Jim Ryder, Alan Baxter. However, Jordan breaks the necklace, and the jeweler he takes them to detects the forgery. Jordan telephones Weldon that he will be coming to collect the real necklace. However, Ryder arranges a fatal car crash instead.

Stanley Young, Addison Richards, Jordan’s partner, asks his friend Michael Lanyard, Warren William the Lone Wolf, for help. Lanyard has given up his shady activities but owes Young a big favor, so he accepts the challenge, much to the delight of his bored valet Jamison, Eric Blore. Meanwhile, Delia Jordan, Joan Perry, Phillip Jordan’s daughter, has met Ralph Bolton, Robert Wilcox on a sea voyage and likes him very much, not suspecting that the man is a crook. He reports to his boss Alberts, Harland Tucker that Lanyard is now involved. Despite Lanyard’s reputation, Alberts is unworried; in fact, he plans to let Lanyard retrieve the necklace and then take it from him.

Lanyard manages to learn that the fence Ryder plans to sell the pearls to is his old friend Emil Gorlick, Montagu Love. Delia follows Lanyard to Gorlick’s hotel. Lanyard confirms Gorlick is to see Weldon and Ryder that night (and that they have never met), then ties up Gorlick and takes his place. Delia, unconvinced by Lanyard’s explanation, peeps through the keyhole of Gorlick’s room. However, she is spotted by the hotel detective, Robert Emmett O’Connor, who unties Gorlick. Delia flees in a taxi, but Gorlick joins her and produces a pistol. However, Lanyard is able to take the necklace before Gorlick arrives. He gives it to Young, who gifts him the fake as a memento.

Young makes the mistake of informing Bolton of the recovery of the pearls. Meanwhile, Ryder telephones Lanyard and demands the necklace for Delia. Lanyard gives the thieves the fake. Lanyard explains the situation to Delia, and they go to Young’s place, but find him dead and the pearls gone.

Lanyard takes the fake necklace from Ryder at gunpoint and locks him and Weldon in a closet. He then has the story spread that the second set of crooks got the fake, and that the real pearls were returned to Delia. Alberts’ gang goes to the Jordan mansion. Lanyard appears, convinces them he has the pearls, and leads them on a car chase to a ferry. Jamison, at Lanyard’s instruction, drives aboard too, with the police trailing him, looking for the man they think murdered Young. When the ferry sails, the crooks have nowhere to run.