One of the frustrating things about Gunsmoke was that Matt Dillon was no Sherlock Holmes. Unlike a lot of other characters of that era, Dillon did not live by his wits. While he often survived thanks to his instincts and his judgment of the character of the people he dealt with, Dillon was not the sharpest knife in the drawer. Having Chester as a sidekick certainly did not help.
In this case, Sheriff Ab Stringer comes to town looking for somebody. Dillon gets a telegraph from the wrong city saying that Stringer is coming from Miami, Texas. Instead of checking it out, by sending a telegraph to Miami, Texas to find out who Stringer is, Dillon does nothing. So Stringer comes to town, and he shines Dillon on, and gets Dillon and Chester to search the town looking for an unknown criminal.
Stringer is played by Harp McGuire, an American actor who spent a few years in Australia doing a popular radio show there. McGuire appeared on Gunsmoke twice, and he died in 1966. Thanks to Chester, fake sheriff Stringer comes across Mrs. Clara Curtin, who is played by Virginia Gregg. Gregg had the warmth of a porcupine in most of her roles, but here she tries hard to play a loving middle-aged wife. Gregg was on Gunsmoke seven times.
Stringer follows Curtin back to her home, where Rob Curtin is watching a calf being born. Something so beautiful is about to end in tragedy thanks to the writing of John Meston. Meston could never write a happy ending. You would think that somebody could get shot in the side and survive, but no.
Stringer confronts Curtin, and recovers bank money they both robbed many years ago, that Curtin had kept hidden away. Stringer decides that because Curtin is reformed, and has a successful ranch, he is no longer trustworthy as a criminal, and must die. This had to be one of the most moronic confrontations in the history of Gunsmoke. At least the final gun-fight did not happen off-camera. As Stringer tells Dillon at the end, "It took you too long to figure it out." Thus two people died because Dillon was slacking off.