The boys and girls of a middle school have, among others, an enthusiastic professor for the history of cinema, who does nothing but talk about western films and heroes and adventurous stories from the Far West, which make one of the schoolgirl dream. The pupils end up identifying themselves in the protagonists of those stories: the brave sheriffs, the perfidious Apaches, the bandits who attacked banks, the beautiful women. Their dreams begin to appear on the screen: thus, the 10-year-old sheriff Billy finds himself bravely fighting in Cactus City against the Apache always on a war footing and against the Mexican "bandidos".