Michael Shayne: Private Detective

Out-of-work private detective Mike Shayne is hired by his friend Hiram Brighton to look after Brighton's spirited daughter Phyllis while the father is away. Phyllis gambles away her money and begins dating the underworld figure Harry Grange, creating tension for the family. The assignment sets up the central dynamic between Shayne, Phyllis, and the criminal elements around them.

Phyllis continues to gamble away her money and grows closer to Grange, much to her father's dismay. The romantic and financial danger surrounding Phyllis increases the stakes for everyone involved. Shayne's watch over her becomes a shield and a warning at the same time.

Wealthy and shady Elliott Thomas owns Banjo Boy and faces a cash crunch. He travels to South America to locate a champion that can be swapped with Banjo Boy, then enlists Grange to spread a massive bet to fix the race. The goal is to generate winnings of around $150,000 through the deception.

Grange is recruited as a shill to spread the word about Thomas's large bet, helping to conceal the substitution plan. The betting circles are manipulated so the substitute horse looks legitimate to bettors. This step is crucial to the scheme's success.

The look-alike horse wins the race, delivering a payoff of about $150,000. The success of the scam hinges on maintaining the illusion for oddsmakers and bettors alike. Tension builds as the money swells and the players' risk increases.

Grange refuses to pay Elliott Thomas the winnings, prompting Thomas to hire Larry Kincaid to pressure Grange. Kincaid heads to Benny Gordon's casino to pressure Grange through Gordon himself. The move heightens the stakes and furthers the web of threats around the participants.

Kincaid meets Grange and learns the backstory behind the plan, including how the scheme was orchestrated. This information makes Kincaid more willing to cut himself in on the pot by blackmailing Thomas. The meeting sets in motion a chain of moves that escalate violence.

Thomas and Kincaid end up in a brawl; Kincaid is killed in the fight, and Grange discovers the confrontation. The murder raises the stakes and compounds the murder mystery. The players scramble to cover the tracks as the truth grows nearer.

With Kincaid dead and the pressure mounting, Thomas resolves to do away with Grange to silence him. The plan moves from financial manipulation to lethal action, pushing the plot toward a direct confrontation. The decision concentrates the danger around Grange and those connected to him.

Grange is drugged after a casino meeting, driven to the woods, smeared with ketchup, and left in a convertible as part of Shayne's attempted lesson for Phyllis. The plan backfires when Grange is found shot dead and Shayne's gun is discovered fired nearby. Sirens approach as the crime scene reveals itself.

Shayne has already tipped the police to a murder in the woods as part of the plan to scare Phyllis. When the body is found and the gun is discovered, the cops close in and arrest Shayne. Phyllis is drawn into the danger as authorities arrive.

Gordon's daughter Marsha stumbles upon the crime scene and is distraught. Gordon uses the situation to frame Shayne and protect his daughter from suspicion. The frame creates a complication in the investigation while preserving the casino owner's own interests.

Shayne pieces together the sequence of events and sets a trap for Thomas in front of the police. The trap forces Thomas to confess to the horse-race plot, Kincaid's death, and Grange's murder. The climax ties together the plot threads and clears Shayne's name.

Thomas confesses the entire scheme, including the horse race plot, Kincaid's death, and the murder of Grange. The body in the bay is uncovered as part of the investigation. The truth unravels the deception and resolves the main conflicts.