<P> The film is based on a short story "Mission With No Record" by James Warner Bellah that appeared in The Saturday Evening Post on September 27, 1947, and the screenplay was written by James Kevin McGuinness . The supporting cast features Ben Johnson, Claude Jarman, Jr., Harry Carey, Jr., and Chill Wills . </P> <P> Lieutenant Colonel Kirby Yorke (John Wayne) is posted on the Texas frontier to defend settlers against attacks by marauding Apaches . Colonel Yorke is under considerable pressure due to the Apaches using Mexico as a sanctuary from pursuit, and by a serious shortage of troops in his command . The action of the movie is set in the summer of 1879 ("fifteen years after the Shenandoah"). </P> <P> Tension is added when Yorke's son (whom he hasn't seen in fifteen years), Trooper Jefferson Yorke (Claude Jarman Jr .), is one of 18 recruits sent to the regiment . He had flunked out of West Point but immediately enlisted as a private in the Army . In a private "father - son" meeting in the commanding officer's tent, Trooper Yorke informs his father that he does not expect, nor want, any special treatment because he is his son . He asks that he be treated like any other soldier--to which the colonel somewhat reluctantly agrees . By his willingness to undergo any test and trial, Jeff is befriended by a pair of older recruits, Travis Tyree (Ben Johnson) (who is on the run from the law) and Daniel "Sandy" Boone (Harry Carey, Jr .), who take him under their wings . </P> <P> With the arrival of Yorke's estranged wife, Kathleen (Maureen O'Hara), who has come to take the underage Yorke home by buying him out of his enlistment, further tension is added . During the Civil War, Yorke had been forced by circumstances to burn Bridesdale, his wife's plantation home in the Shenandoah valley . Sgt . Quincannon (Victor McLaglen), who put the torch to Bridesdale, is still with Yorke and is a constant reminder to Kathleen of the episode . In a showdown with his mother, Jeff refuses her attempt buy him out of the Army by reminding her that not only the commander's signature is required to discharge him, but his own as well; and he chooses to stay in the Army . The tension brought about in the struggle over their son's future (and possibly the attentions shown to her by Yorke's junior officers) rekindles the romance the couple once felt for each other . </P>

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