El Juramento (secret lies) is the title of a Spanish-language telenovela produced by the United States–based television network Telemundo.

The show starred Natalia Streignard, Osvaldo Ríos, Ricardo Chávez and Dominika Paleta, and is also known as Secret Lies.

El Juramento tells the story of Santiago, a dashing hero who sets out to avenge the death of his brother, Diego.

A wealthy man, Teodoro Robles Conde, owns the house and lives with his two nieces—and our hero knows one of them caused Diego's suicide, but which one?

Meanwhile, Santiago finds himself falling in love with Andrea but fights hard to resist his feelings in order to keep his oath to Diego.

[3] This was the first show filmed at the new Estudios Mexicanos Telemundo in Mexico City, with location shooting in Hidalgo and Querétaro.

[4] Telemundo, which had used The Gaby Espino Project as a working title,[2][permanent dead link‍] planned to air the serial from Monday to Friday for 130 episodes, but the show was shortened because ratings were unimpressive.

(The show was also known as La Mentira, or The Lie) It was delayed when the original Santiago, Fernando Carrillo was fired and replaced by Osvaldo Ríos.