Relaciones Peligrosas, originally known as Fisico o Quimica, is a Spanish-language telenovela produced by United States-based television network Telemundo Studios, Miami. It is an adaptation of the Spanish television series Física o Química. It has Sandra Echeverría, Gabriel Coronel, Maritza Bustamante, Gonzalo García Vivanco, Jonathan Freudman, Mercedes Molto, Carlos Ferro, Daniela Navarro, Renato Rossini, Kevin Aponte and Ana Layevska in the leading roles of the plot.

14-year-old kid Enrique sees himself as an adult, and who has a passion for the latest technology.

Two love stories intertwine the past and present Puerto Rico. In the first, the only woman in history to be sentenced to death in the island. In the second, an accident completely changes the life of a pianist, who must get used to his new physical situation.

Adalberto's life turns upside down when his daughter Sylvia announces she's getting married.

Sara Rodríguez faces a mid-life crisis, succumbing to the media clamor for a youthful appearance with everything from collagen to breast enhancements, as she faces her menopause. What she really needs is her workaholic husband's attention. After turning the world upside, Sara finds the solution where she least expects it.