The imposter topic is very rare in a western:we often find it in a classic detective film like "no man of her own"(1950) and its French mediocre remake "I married a shadow" (1982).Except for the short prologue ,first half looks like a psychological suspense.Second part is more eventful,although not at the expense of Alan Ladd character's frames of mind.
The hero actually is in need of a family;we know it from the start,Alan Ladd's wistful face tells it all.Love interest-which might be some kind of faux incest-is not as convincing as the hero's searching for haven ;it's a pity that the mother's character is not more present because she is,more than Mona Freeman's one,the keystone of the story.
Also a work of redemption ,because Ladd will try to redeem himself ,and a plea for peace and understanding,proof positive that a western does not need a violent showdown to be successful.The Rio Grande becomes a beautiful symbol,as human as political,and the scene when the Father takes in the two men on its banks has a biblical grandeur.
Rudolph Mate shows here that a B western can sometimes be deeper than so-called" A grade" classic ones.