Francisco Romero is a small-town teacher who decides to try his luck in Mexico City. He joins the faculty of Prep school number 10 "Rosario Castellanos" and soon realizes that his work is more demanding than he expected; in addition to having to prove himself as a teacher, he must prove himself as a human being. He will also find that - in order to make a difference with his students - he will have to assume the roles of counselor, psychologist, doctor, and even detective. The themes this story deals with are: dropping out of school, teen pregnancy, street gangs, men who abuse their stepdaughters, teenagers forced to work to support their families, and alcoholic parents who lead their children down the same path.