Distinguished barrister Anthony Keane is hired to defend the beautiful and enigmatic Mrs. Maddalena Anna Paradine, who is accused of poisoning her blind husband. As Keane delves into the case, he finds himself increasingly captivated by his alluring client, much to the distress of his loyal wife, Gay. The case unfolds amidst the sumptuous settings of London’s legal circles and country estates, with intricate interactions between the characters revealing hidden motives and past relationships. Keane's dedication to uncovering the truth leads him to visit the Paradine estate and question the household staff, including the mysterious valet André Latour.

As the trial proceeds, Keane's professional judgment becomes clouded by his growing obsession with Mrs. Paradine, jeopardizing his career and marriage. Tension mounts in the courtroom as revelations about Mrs. Paradine's past and her true feelings towards her husband come to light. Keane's struggle to balance his ethical duty and personal emotions culminates in dramatic courtroom confrontations. The story explores themes of love, betrayal, and justice, keeping viewers engrossed until the very end.