Dial M for Murder

Tony Wendice, a former tennis player, marries Margot primarily for her wealth. After marrying her, he abandons his tennis career to sell sports equipment to support their lifestyle.

Margot reminisces about her past relationship with Mark Halliday, an American crime scriptwriter. Despite breaking it off, their feelings linger, and Margot deceives Tony about the extent of their relationship.

A blackmailer demands £50 from Margot for a stolen letter from Mark. Margot pays the money but does not receive the letter back, raising tensions in her life.

Unbeknownst to Margot, Tony spends a year plotting her murder. His preparations include gathering money for a contract killer and stealing one of Mark's letters to manipulate Margot.

Tony meets with Charles 'C.A.' Swann under the guise of discussing a car deal, but he blackmails Swann into agreeing to murder Margot instead. It sets the stage for the impending crime.

Tony orchestrates a stag party to create an alibi for himself while Margot is at home waiting for a phone call. He plans for Swann to murder her during this time.

Swann attempts to murder Margot as planned, but she fights back fiercely. In a struggle, she grabs a pair of scissors and fatally stabs Swann, dramatically altering Tony's plan.

Panicking over the unforeseen turn of events, Tony quickly concocts a new narrative to frame Margot as the attacker. He plants evidence to mislead the police and save his own skin.

During the police investigation, Inspector Hubbard grows suspicious of Margot based on the evidence Tony planted. The trial unfolds under tense circumstances, targeting Margot.

Margot is found guilty based on the misleading evidence and is sentenced to death. Tony's coldly calculated plan seemingly comes to fruition as he watches her life unravel.

Desperation drives Mark to propose a plan to Tony, where he would confess to the murder to save Margot from execution. He presents an elaborate but risky plan that coincidentally mirrors the truth.

Inspector Hubbard begins to see through Tony's web of lies. He investigates the money Tony has been spending and finds evidence that contradicts Tony's claims.

Hubbard discovers that the key found in Swann's pocket is not Tony's but Swann's own. This revelation leads him to understand the true events that transpired, increasing his suspicion towards Tony.

Hubbard sets a trap for Tony, leading to a tense confrontation. A series of events causes Tony to realize he has been outsmarted, resulting in his eventual capture.

After all the layers of deception peel away, Margot is released from prison. Tony's plans crumble as he faces justice for his actions while Margot is freed from the looming execution.