A Kentucky slave (Davis) fights for his freedom from a cruel overseer whose mistress eventually joins him and the other slaves in their revolt.

At New Mexico's Empire Zinc mine, Mexican-American workers protest the unsafe work conditions and unequal wages compared to their Anglo counterparts. Ramon Quintero helps organize the strike, but he is shown to be a hypocrite by treating his pregnant wife, Esperanza, with a similar unfairness. When an injunction stops the men from protesting, however, the gender roles are reversed, and women find themselves on the picket lines while the men stay at home.