"Corazón indomable" (Wild at Heart) is a Mexican telenovela produced by Nathalie Lartilleux for Televisa. It is a remake of the 1994 Mexican telenovela Marimar. Ana Brenda Contreras and Daniel Arenas star as the protagonists, while Elizabeth Álvarez stars as the antagonist, with the special participation of César Évora. Maricruz Olivares lives with Ramiro, her maternal grandfather, and Solita, who is deaf-mute and whom they found abandoned when she was a little baby. She lives in a shack located in the middle of nature, near the Narvaez´s ranch property line. Miguel and Octavio are siblings and they both own the Narvaez´s ranch, which is mortgaged because of the bad administration Miguel, the older brother, has made. Octavio is a pilot and arrives in the ranch in need of money since he has lost his job and wants the lands to be sold. He doesn´t imagine that soon he will forget this purpose and will discover that the earth, the sowing and sharing with the workmen become a source of passion for him.
Octavio meets Maricruz while he is traveling around the lands and catches his foreman mistreating her. Regardless of her humble origins, he defends her as a gentleman. Immediately, he is trapped by her sympathy and beauty. When Octavio discovers the malice with which Lucia, his sister-in-law, treats Maricruz, he gets really angry and decides to marry Maricruz in order to teach his brother and Lucia a lesson. However, when he receives a tempting job offer as a pilot, Octavio leaves the ranch and asks his brother to give Maricruz his part of the land. Lucia and her cousin Esther set a trap to Maricruz who is accused unjustly of being a thief and ends up in jail. Fortunately, a lawyer believes in her and achieves her freedom; but when she returns, she is shocked to discover that her grandparent died during a fire.
Maricruz leaves to the capital city with her sister Solita and starts working as a maid at Alejandro´s house, who happens to be her father, without any of them knowing about the bond between them. Maricruz gains his trust and love, and he helps her to get educated and become a high society woman. In the meantime she accepts to help him with the administration of the casino in a cruise ship, posted in Isla Dorada. There she will have to face the ambition of the Canseco sisters Carola and Raiza, who keep their lives comfortable at Alejandro´s cost. Alejandro´s butler discovers Maricruz´s birth certificate where her real name appears: Maria Alejandra Mendoza Olivares. In order to avoid the big impression that could kill Alejandro, since he suffers from a heart disease, he decides not to reveal him that Maricruz is his daughter, but he does tell Maricruz the truth and she feels very happy with such news. Miguel informs his brother that Maricruz disappeared after her grandfather´s death. Octavio arrives in the casino, invited by a friend. Octavio´s good looks catch the interest of sophisticated women and he feels flattered, but he cannot forget Maricruz. He doesn´t imagine that the humble youngster who used to be his wife is no other than the elegant Maria Alejandra Mendoza, the manager and main host of the casino.