This program is the first of two parts that deal with the history of Mexican cinema. ''The Great Decades'' is the saga of a film industry born at the turn of the twentieth century into a culture marked by a long and impressive history of visual talent. How a rich culture of silent film was created and how Mexican film became the fifth largest producer in the world during its golden age of the 1940's and the first few years of the 1950's remain the central concerns. The effect of private and public support from the US is considered, but above all, the success of the industry is considered in relation to the talent of the industry's directors, actors and technical specialists.—Clío TV