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.

Ga-eul is six years into her marriage but her trouble with her husband brings her to depend on alcohol. Hee-mang is a writer who lives next door but can't stand the fighting going on at Ga-eul's house and makes his way over there one day. Ever since then, Ga-eul goes over to Hee-mang's house to have sex everytime she fights with her husband. Hee-mang is confused at her behavior and gradually falls for her. Then Ga-eul slowly resolves things with her husband but Hee-mang asks to talk with the three of them...

Juliette Merteuil and Valmont is a sophisticated couple, always looking for fun and excitement. Both have sexual affairs with others and share their experiences with one another. But there is one rule: never fall in love. But this time Valmont falls madly in love with a girl he meets at a ski resort, Marianne.

A woman is murdered by a sleep walking psychopath, who used to be a client of her husband. Now, her husband must prove who's actually responsible for his wife's death.

The young scion of a rich lineage should get married and give an heir to the family. But no one wants to touch his girlfriend before marriage and instead consoled with the beautiful waitress. But things get complicated and suddenly strange deaths begin to hit the family members.

Erika and Ryan are a happily married couple living in a high rise Apartment in Atlanta, Ga. Everything is going great until Erika meets a handsome, mysterious man in her building and they start having an affair.

Hieronim Śpiewankiewicz is the chief cashier in one of the banks in Warsaw.

Pilates instructor, Amelie Didot, begins a steamy love affair with one of her handsome clients, journalist Pierce Dalton, but the duo soon find themselves dangerously intertwined after Amelie comes face to face with a masked woman following a murder. When it’s revealed the killer has an erotic obsession with Pierce, Amelie becomes a target in the middle of a deadly love triangle.

Holt plays police lieutenant McHenry, while Graves is his friendly rival, crime reporter Wally Cook. After the two men verbally duel over a variety of details, they hunker down to business, that of solving the murder of a lawyer who was in the midst of reading a will to a motley collection of heirs.

Sharon Blake is a successful career woman who has a passionate affair with a possessive man. When she tries to break off the relationship, she uncovers the dark side of her former lover, who starts stalking and harassing her.

Elderly millionaire James Rance, whose only passion is chess, warns his grandson Tommy, who missed the previous evening's game because he played poker with his uncle Gilbert, that should he miss another game, Gilbert will gain the boy's inheritance. During another poker game the next night, Gilbert provokes a fight between Tommy and another player that results in the other player's supposed death. Meanwhile, Terrence Redmond, the guardian of an orphan he found while fighting in France, falls in love with Dawn Moyer.

Georges Duroy travels through 1890s Paris, from cockroach ridden garrets to opulent salons, using his wits and powers of seduction to rise from poverty to wealth, from a prostitute’s embrace to passionate trysts with wealthy beauties, in a world where politics and media jostle for influence, where sex is power and celebrity an obsession.

Olivia battles insomnia after her son's death, but her friendship with Shane evolves into an affair. When Shane's wife vanishes, Olivia's sleepwalking intensifies and she becomes a suspect.

Youngwu and Jiyoung have been married for ten years and have long since grown apart. He, a publisher, is having an affair with a writer and she, a housewife, feels drawn to a gentle young Muslim she meets named Kerim. When he is obliged to leave the country she decides to follow him to Varanasi. Leaving her husband a note saying that she is away visiting relatives, she spends her time wandering along the banks of the Ganges and down the busy streets of this Hindu city in search of Kerim. When he turns on the television her husband is astonished to see his wife covered in ashes, emerging from a restaurant that has been bombed by terrorists. Youngwo decides to head for India to find his wife and obtain an explanation for her behaviour.