Marimar is a poor, innocent girl who lives with her grandparents in a hut on the beach, in "San Martín de
la Costa", by the ocean. She falls in love with Sergio, a soccer player and the son of a wealthy man who has beachfront property.
To spite his father and his young stepmother, Sergio marries Marimar; however, he falls deeply in love with her.
Sergio's stepmother, Angélica, despises Marimar because of her poverty, naïveté and innocence. She cruelly
embarrasses Marimar, often demeaning her as an individual in front of her friends and guests. Sergio decides to go away to
earn enough money to take Marimar away from his father's house. After leaving Marimar alone with his family, Angélica frames
Marimar and tells the cops that she stole a bracelet from her. Marimar is sent to jail.
While Marimar is in jail, Angélica orders one of her servants to burn down her grandparents' hut with them
inside, killing them both. She then forges Sergio's handwriting and writes a letter to Marimar stating that he never loved
her and wants a divorce. At this moment, Marimar decides that she will exact revenge from Sergio, his father, and Angélica.
With nothing left for her in San Martín de la Costa, Marimar relocates to Mexico City after her release from jail. She is offered a housekeeping position at the home of a wealthy older man, Gustavo
Aldama, who takes a liking to Marimar and decides to train her to be an educated young lady. Marimar then assumes the identity
of "Bella Aldama" and discovers that she is actually Gustavo Aldama's daughter.
To show off her transformation to the world, Gustavo Aldama decides to take her into town, to the same places
where, coincidentally, Sergio and his friends are. Fueled by revenge, "Bella" uses every opportunity to seduce Sergio, then
reject his advances in order to spite him. After her father's death, Marimar inherits his wealth. Still fueled by revenge,
she hatches an elaborate plot to bankrupt Sergio's father and humiliate his stepmother Angélica, leaving them virtually homeless
while Marimar becomes the proud owner of all their former properties.
After Sergio divorces Marimar (though he is still secretly in love with her), Angélica is badly burned in
a car accident and dies. In dire straits, Sergio marries a rich young woman, Natalia, who despises Marimar. Natalia later
learns that she has a brain tumor, and after her surgery, she is so happy to be alive that she divorces Sergio so he can be
free to marry Marimar. They finally marry.