Based on

Movies like The Call of the Heart (1928)

Molly O'Day and her brother, Josh, are homesteading on and trying to make a living on a piece of government land, but local rancher Dave Crenshaw claims the land is part of his holdings, and he and his henchmen try to drive the O'Days off. Cowhand Jerry Wilson and his dog, Dynamite, come to their aid against Crenshaw.