Regina Bárcenas is a Senator for the party that governs the country, and the wife of the current head of government of the city, Alonso San Román, who aspires to the presidency of the country. As part of his political maneuvers, Alonso suggests Regina convince Senator Gerardo Martinez to join his candidacy, regardless of the fact that Gerardo, the leader of the opposition, is in love with Regina. Regina feels used and her marriage begins to suffer serious problems with the arrival of Cecilia Aguilar, who is in charge of the press area of the Government Headquarters. Regina is unaware that Cecilia is her half-sister, the fruit of a clandestine relationship and that she will not rest until she seduces Alonso and destroys her. Later, members of his party propose Regina to run for president in place of Alonso. Regina hesitates at first but discovers a series of illicit businesses of her husband and her father, so she joins an independent party to face her husband in elections.