Cleve Marshall, an assistant district attorney, falls for Thelma Jordon, a mysterious woman with a troubled past. When Thelma becomes a suspect in her aunt's murder, Cleve tries to clear her name.

In London, barrister Anthony Keane takes the case of Maddalena Paradine, a beautiful woman accused of poisoning her blind husband. Though happily married, Keane becomes infatuated with his enigmatic client and convinced of her innocence. His obsession clouds his judgment as he builds a defense implicating her servant, André Latour—an act that leads to devastating consequences both in court and at home.