Marcia Cisneros, accused abroad of a crime she didn't commit, is sentenced to 35 years in prison. Esteban Lombardo, her husband, not only considers her a murderer but also an adulterer, who killed her lover as a cover for her betrayal. He even doubts he is the real father of their youngest daughter. Esteban's sisters, his partners and wives, testify against Marcia. All of them have their own reasons to hate her. Esteban leaves Marcia hanging out dry and files for divorce.

Confident of her innocence, and certain that the murderer is among her ex-husband's friends, Marcia studies law to reopen the case.

Upon returning to Mexico, Esteban's older sister, Lucrecia, places a portrait of a stranger and she and Esteban fabricate a lie, assuring Marcia's children, Hugo and Lucía that their mother died in an accident. The kids grow up adoring the virtuous woman in the portrait.

Twenty years later, a lawyer arranges an early release and Marcia returns to the country, resolved to recover her children and clear her name. Father Jose, her confidant and protector, notifies her that Esteban is engaged to Paula and that in the eyes of her children, she is dead.

Marcia summons all the suspects, who are shocked to see her. Regardless of the bitterness, Marcia and Esteban feel the love and desire resurface between them. To win over her children and investigate each of the suspects, Marcia changes her name and introduces herself as Marisa Jones. 

Marcia forces Esteban to break up with Paula and marry her, becoming The Stepmother to her own children, who do nothing but despise her, while she puts the puzzle together and risks her life trying to expose the murderer. Lucrecia and Esteban's friends conspire to destroy her. Marcia unmasks the suspects, one by one, exposing their dark secrets and finally discovering the murderer. 

Esteban admits his mistake and begs her forgiveness. Marcia sees that they were both victims of jealousy and the selfishness of others, so they give each other a second chance. Undeterred, Marcia regains the love of her children, as she is cleared of any guilt.