Lancer is the story of a rancher who struggles to hang onto his vast holdings in California's San Joaquin Valley with the help of his two sons and his ward. Scott, whose mother died in childbirth, is Murdoch Lancer's older son. He was raised by his maternal grandfather in Boston. Younger son Johnny was taken from his father by his Mexican mother when he was only around two. He grew up around the Mexican border and went by the name Johnny Madrid under which he earned a reputation as a fast gun. Deservedly so, apparently, as men from his past occasionally show up to cause problems for Johnny and his new-found family. Teresa O'Brien, daughter of Murdoch's murdered ranch foreman is Murdoch's ward and a surrogate sister to the two boys.