Eleven year old Stan Adams is the young hero of a story of homesteaders versus cattlemen and of his own growing up as it is centered around the training of a mustang X O. When X O is left in his charge for the winter, Stan a homesteader's son goes to a friendly cattleman to get a job. Through the winter, X O is trained out of a bad upbringing and Stan learns the ropes of cowpunching as well as triumphing in a feud with another rival cowman's son.