Paulino Córdoba (Roberto Blandón), Gabino Roura (Sergio Goyri), Rodolfo Huerta (Francisco Gattorno), and Matías Quiroga (Salvador Sánchez) have been friends since their childhood; however as adults, their priorities change and a sin threatens to destroy their friendship. Paulino is the owner of the hacienda El Milagro, which grows and sells apples, and is married to Rosario (Daniela Castro), with whom he has two children, César and Lucrecia (Daniela Aedo, Maite Perroni). Rosario has always shown preference for her son and openly rejects her daughter. Rosario's servant, Delfina (Magda Karina), essentially raises Lucrecia alongside her own son, Manuel (Aldo Gallardo), and Lucrecia and Manuel become like siblings.
Lucrecia's best friend, however, is Julián Huerta (Adriano Zendejas, Eugenio Siller). Both share the same likes and eventually, as the years pass, come to also share a great love.  Gabino Roura is a clever and ambitious man who kills his wife, Inés (Lucía Méndez), in order to seize her fortune.  Gabino manipulates his friends and his children, Carmelo (Armando Araiza) and Teresa (Gabriela Carrillo). He is the owner of the best farming lands, which he rents out to Paulino in order to control the distribution and marketing of the apples.  Rodolfo is the teacher in the town of San Pedro; he is an upstanding and hard-working man who is married to Justina (Sabine Moussier), a sensual woman who is dissatisfied with her husband's simple lifestyle, and they have two sons, Julián and Josué (Diego Amazurrutia). It is Justina Almada who detonates the serious conflicts that threaten to destroy the friendship between Rodolfo, Paulino, and Gabino. Matías Quiroga, the priest of the town of San Pedro, sees with a heavy heart that his friends are now enemies and are the principal obstacle for Lucrecia and Julián's love. 
Unfortunately, chance has seen Lucrecia and Julián involved in an accident that costs César his life, and although they are both innocent, Rosario believes them to be responsible.  Depression seizes Rosario, who always merely tolerated her daughter's presence. Rosario's resentment forces Paulino to send their daughter away and to distance himself from Rodolfo Huerta's family.  As a result of his infamy, Julián is tormented by the denizens of San Pedro, who nickname him El Chamuco (Spanish slang for "the Devil"),  the pain of which he must carry for the rest of his life. 
Years later, Julián and Lucrecia come across one another and their love blooms once more.  Although their parents are in opposition, Julián and Lucrecia are prepared to fight for their love, and they count on the support of Delfina, her husband Modesto, and Manuel, who in spite of his love for Lucrecia helps her to be happy with Julián. Modesto, foreman of El Milagro, is a country man who has a small parcel of land on which he grows corn and, upon marrying Delfina, forms a loving family with her and Manuel.  Lucrecia does not return to San Pedro alone, but accompanied by her cousin, Renata (Jessica Coch), an envious girl who is prepared to seize everything that is Lucrecia's.  In San Pedro, Paulino suffers an economic crisis and Gabino demands Lucrecia's hand in marriage. However, the jealous Carmelo steps in and kills his father.  Julián is unjustly accused of this crime,  and Lucrecia is forced to marry Carmelo in order to prevent her father's financial ruin and to save Julián from jail.  Julián leaves San Pedro for Veracruz, convinced that Lucrecia betrayed him. 
Three years pass.  Lucrecia lives drowning in sorrow as Carmelo's wife; furthermore, she has lost the hacienda El Milagro. In San Pedro, the people talk of the arrival of an outsider who has bought Los Alamos, and Lucrecia discovers that this outsider is none other than Julián Huerta, who is now engaged to his ex-girlfriend, Lorena Mendizábal (Altair Jarabo). Carmelo finds out that Julián has returned and a war unleashes between the two for Lucrecia's love. Julián plans on leaving Lorena, but she lies to him that she is pregnant with his child. Meanwhile, Lucrecia gives Carmelo divorce papers, and he responds by ripping up the papers and raping Lucrecia. Lucrecia returns to her parents' home and struggles with the rape, telling no one but Delfina.
Carmelo, furious that a judge has approved of Lucrecia's request for divorce, takes revenge by burning down the warehouse full of apples that Paulino owns; Paulino is accidentally trapped in the warehouse and dies from smoke inhalation. At his funeral, Lucrecia faints and discovers that she is pregnant, but does not know who the father is. Rosario finds out that Lucrecia was raped and for once takes Lucrecia's side; however, when she finds out her daughter is pregnant, she urges her to have an abortion. Carmelo, on the run from the police, kidnaps Lucrecia, but Julián saves her; meanwhile, Renata is shot by accident and dies on the way to the hospital. After returning home, Lucrecia confronts her mother about the hatred Rosario always shown towards her, and she finally admits her secret: Lucrecia is not only Rosario's daughter, but she is also her sister, because Rosario was raped by her father and became pregnant with Lucrecia as a result.
Lucrecia receives a letter in the mail that her divorce against Carmelo has been finalized, then a few days later, she goes to the church for her and Julian's wedding. Lucrecia and Julián are married as Rosario watches her daughter's wedding from afar. Time passes, and Lucrecia gives birth to a son whom she names César, in memory of her brother. Lucrecia leaves Rosario with César so that they can spend some time getting to know one another. After Lucrecia returns to the room she sees her mother and son are not there, she assumes the worst. However, her mother has left the baby on the bed in Lucrecia's brother's room, and goes to the river where her son died and commits suicide by drowning herself.
Three years later, Lucrecia stands by the river and throws two white roses into the river: one for her brother and one for the mother. Although saddened by the loss of her family, she is joined at the river by her husband and son, whose strong blue eyes reveal him to be Julián's child, and the three live happily ever after.
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