El noveno mandamiento (Lit: The Ninth Commandment / English title: Forbidden Attraction) is a Mexican telenovela produced by Lucero Suárez for Televisa in 2001.

The story occurs in a small Veracruz town where brothers Rodrigo and Bruno Betancourt vie with each other for Ana's love, thus breaking the ninth commandment, not to covet thy neighbor's wife.

Clara lives tormented with the thought that she will never marry, since in that small town, the only bachelor is her sister's fiancé, Leandro, who initiates an uncontrollable passion in her.

Clara attempts to persuade him to call off the wedding saying that Isabel only has a short time to live, but he refuses to listen.

Leandro is extremely unhappy attached to a woman whom he loathes, but does not give up and finds proof that Clara tricked him into sleeping with her.

Tied by guilt and thinking that Isabel is with another man, Leandro stays with Clara in a rocky and obsessive relationship.

Leandro unburdens himself with alcohol, always debating to stay or to go; Clara living with his rejections, while always desperately trying to make him love her, or at least keep him by her side.

Ana also meets the neighbors, Rodrigo and Bruno Betancourt, heirs of the best lands in that region.