John Wayne delivers a memorable performance in this film, taking on the role of "Dan Somers," a cowboy who sets out to strike it rich by prospecting for oil around the year 1900. His idea involves partnering with Oklahoma’s Native American population to develop their land, but he runs into trouble from local oilman "Jim Gardner" (Albert Dekker), who also wants those lands – and intends to exploit them unfairly. A stroke of good fortune, along with a connection in authority, gives "Dan" an opportunity, though the question remains whether he can find the oil and get it sold before time runs out. Wayne’s portrayal feels different from many of his previous roles; there's more depth to his character, the lines feel more natural, and his inherent charm is allowed to come forward. It strikes me that Wayne and Errol Flynn shared a similar need for strong supporting players who they could collaborate with repeatedly, and in this case, "Gabby" Hayes’ energetic presence keeps things moving at a good pace. While “Cathy,” played by Martha Scott, doesn't have much of an impact on the story, she still adds something to this David-and-Goliath narrative, particularly because both men are interested in her. I would definitely consider this one among his best work.

Source on TMDB