Mike Hammer: Murder Takes All

Mike Hammer was framed because the real mastermind, Helen Durant, needed a scapegoat. After her husband Carl and Johnny Roman stole telethon money, Helen orchestrated a revenge scheme that involved eliminating everyone involved. By planting evidence pointing to Hammer and making him the prime suspect, she could distract from the real crimes while carrying out her plan.

Earlier, Johnny Roman mentions Barbara Leguire stole something from him, hinting at the underlying theft.

Johnny Roman was killed by Helen Durant through a booby-trapped explosive device. Helen orchestrated his death as part of her revenge plot after Johnny, who had affair with her, stole telethon money along with her husband Carl. The explosive trap was set to eliminate Johnny and make it appear as though someone else was responsible.

The mysterious booby trap that kills Johnny is the first sign that someone is systematically eliminating people connected to the telethon scheme.

Helen killed everyone because she was revenge for Johnny Roman taking advantage of her when she was a young chorus girl, and later discovering that her husband Carl was stealing telethon money alongside Johnny. She wanted to destroy the telethon operation and punish everyone involved in the affair and the theft, even though her husband Carl was also part of the scheme.

Helen's obsession with recovering Johnny's diary, which contains details of their affair, establishes her deep personal vendetta.

Johnny Roman and Carl Durant were stealing money from a charity telethon they were working on. They created false clues like the diary and account book to cover their tracks. When their scheme began unraveling, Helen used the situation to eliminate them both and frame others for the murders.

The misidentified account book and diary that Brad and Carl search for are the false clues left behind by the thieves.

Amy Durant learns that Johnny Roman was her biological father, though she was raised by Carl Durant, who she believed was her real father. Helen had hidden this truth, and when Amy discovers Johnny was her father, it shatters her understanding of her family.

The revelation comes at the prospector's cabin where Amy admits Johnny Roman was her biological father.

Helen needed someone to frame for the murders to keep suspicion away from herself while she carried out her revenge. Hammer was the perfect patsy because he was a famous detective who would naturally investigate the crimes, making him an easy target for the frame-up.

The anonymous wedding chapel invitation draws Hammer into Helen's web, setting up his involvement.

Carl Durant was killed by a booby-trapped door on Helen's yacht. When he went to find Helen seeking the account book, the door triggered an explosive device that destroyed the entire yacht. Helen had set the trap expecting someone would come looking for her.

Earlier, Helen asks Hammer to guard her on the yacht, knowing the danger she had prepared.

The diary contained details about Helen's affair with Johnny, which she needed to destroy to protect the children's clinic where she worked from a scandal. She was willing to pay anything to recover it and keep the truth about her past from damaging the clinic's reputation.

Helen explains at her clinic that she must buy back the diary to avoid scandal at the children's clinic.

William Bundy was revealed as the person who attacked Hammer at the hotel. Security supervisor Leora Van Treas identified Bundy as the attacker, though Bundy was later murdered himself as part of Helen's larger scheme to eliminate everyone connected to the original crimes.

The attack on Hammer from the hotel roof occurs while he's chasing a suspect, leading to his hospitalization.

Bundy was murdered because he was part of the original criminal operation connected to Johnny and Carl. Helen eliminated him to silence anyone who could reveal the telethon theft scheme. When Hammer and Brad return to Bundy's ranch, they find him already dead, and police arrive forcing them to flee.

Brad sets up the trip to Bundy's ranch, which leads to the discovery of his body.