Sons of Katie Elder, The (1965): Hathaway’s Western, Starring John Wayne and Dean Martin

In Henry Hathaway commercially popular but artistically mediocre western, “The Sons of Katie Elder,” John Wayne, in his first role after a serious bout with cancer (“I Licked the Big C”) plays John Elder, the eldest and toughest of four brothers. 
Elder’s siblings are Tom (Dean Martin), a cardsharp and conman, Matt (Earl Holliman), a quiet one (Earl Holliman), and Bud (Michael Anderson Jr.), the youngest and the hope of the family. 
The quartet gets together at the funeral of their mother, a noble and brave woman, who had died in poverty, whereupon they set out to investigate their father’s death, which occurred on the night he supposedly gambled away his ranch to the town’s boss. 
Sheriff Billy Wilson (Paul Fix) and his young, inexperienced deputy, Ben Latta (Jeremy Slate), warn the brothers to stay out of trouble, which, of course, does not help. 
Problem is, there are only two witnesses, Morgan Hastings (James Gregory) and his son, Dave (Dennis Hopper). To protect themselves and their illegal acquisition, and to cover the murder of the Elders’ father, the Hastings try to incriminate the brothers for the sheriff’s murder. Blamed for the vicious killing, the brothers have no choice but to give themselves up and to be taken to Loredo with a posse.
Mary Gordon (Martha Hyer), Ben Latta’s love interest, visits the brothers, bringing them food, while criticizing them for neglecting and deserting their mother.
In an ambush, Matt Elder is killed and Bud is wounded, but Wayne’s Elder becomes even more committed to avenge the multiple deaths in his family, telling the deputy sheriff in a characteristic manner: “This is something I have to do for ”myself.” 
After killing the boss and clearing the family’s name, Elder fulfills another promise, sending his younger brother to college.