The Lone Wolf Meets a Lady

At the Penyon mansion, Bob Penyon gives his fiancée Joan Bradley a valuable diamond necklace, a cherished family heirloom. Rose Waverly phones Clay Beaudine to report that the couple has just left with the jewel. The gift sets the stage for a chain of schemes and motives centered on the necklace.

Peter Rennick confronts Joan and forcibly takes the necklace. An unseen murderer shoots Rennick and steals the jewelry, leaving Joan terrified and on the run. The crime kicks off the central mystery that drives the rest of the plot.

A speeding Jamison nearly runs Joan down on the street as she flees. A motorcycle policeman arrests Joan, Jamison, and Jamison's employer, Michael Lanyard, the famed jewel thief known as the Lone Wolf. Joan blurts out her involvement in a murder, prompting Lanyard to step in with a plan.

Lanyard escorts Joan back to her apartment, examines the scene for clues, and provides her with a confident cover story for the police. He uses his wits and charm to keep the arrest from sticking to Joan. The uneasy alliance between them begins to form.

Beaudine waits outside and spots Lanyard and Joan leaving, convinced they are colluding to steal the necklace. He closes in, ready to confront them and demand answers. The pursuit heightens the tension between the rival players.

Inspector Crane arrives and initially believes Joan's story. He discovers the door wasn't forced and a key matches the dead man's lock, which makes him hesitate. He intends to question her, but allows her time to dress and to be followed instead of jailed immediately.

Joan looks up Lanyard's address in the telephone directory and heads there to seek help and more information. The move signals her deepening reliance on the Lone Wolf, whether she likes it or not. The pursuit grows more personal as she tries to outsmart the police.

Beaudine reaches Lanyard's place first and confronts him, convinced that he and Joan are working together to pawn the necklace. Joan arrives soon after, and Jamison restrains Beaudine at gunpoint. Lanyard learns about the incriminating key and that Joan escaped with ease.

When Crane shows up, Lanyard hides Joan in a secret compartment, keeping her out of sight. After the police and Beaudine depart, Lanyard and Joan go to see Nick, a fence, to learn whether the necklace is being sold on the market.

Beaudine returns to Lanyard's place while Lanyard is away and recognizes the people in a newspaper photo of those present when Joan received the necklace. He locks Joan and Jamison up and demands the necklace be brought within 15 minutes, while Jamison's recording device secretly captures the exchange.

Bob Penyon and Lanyard arrive after Beaudine leaves. Nick informs Lanyard that the necklace had been broken up and sold piecemeal a year earlier. The recording confirms new clues, and they race away to pursue the truth.

The duo obtain Peter Rennick's address from his dry cleaner, who then calls Inspector Crane. They locate Beaudine's dead body, confirming the case's murders are linked to the necklace. The clue pushes them toward locating the killer.

Crane and his men close in and arrest Lanyard on the suspicion of the murder, though his cleverness makes the case tricky. Lanyard remains defiant, using wit to stay in the game while keeping the real killer at large. The stake is raised as the detectives close in.

Bob Penyon pulls a gun to force a confession, and Lanyard uses a phone to alert Joan that the murderer is identified and that the necklace lies in the river beside her apartment. The river clue becomes the revelatory centerpiece as the suspects are drawn toward the waterfront.

Beating the others to the reveal, Lanyard leads Crane to Joan's place where van Wyke, Arthur Trent, and Bob's mother drive up. Lanyard declares van Wyke as the killer, resolving the mystery and exposing the necklace's plan. The truth brings a tense climax to the pursuit.