The other comments here on IMDB all summarize the plot in great detail-- so why watch the show?
WELL.........
It's a very strong episode, expertly written and directed. There's a TON of excellent dialogue and character interaction--- at the end you almost feel as if you've experienced a full-length film; it's that good.
Plenty of surprises--especially as the episode is gathering momentum to the end. There's also a nice musical interlude featuring the fabulous singing of Ken Curtis, which really enhances the bond between Festus and Bucko-- friends 'til the bitter end...with even a wisecrack or two as they are about to meet their doom.
Elizabeth McRae (April) is her usual engaging self, often coming perilously close to outright caricature....but still managing to control it.
Lots of edge-of-the-seat tension as Matt (and April) try to pull the truth out of the drunken, cowardly "Pop" (Roy Barcroft)-- while back at the office, Chester its trying to snag the keys to let himself out of jail, and on the other side of town, a double-lynching is about to take place in a dramatically lit barn (the brooding, intense nighttime photography of these hour-long episodes CONTINUES to be a great asset in the visual dramatics). All of these plot elements are brought together and resolved brilliantly by writer Les Crutchfield.
Gunsmoke was the quintessential "adult" Western, and this episode-- while not intentionally profound or "probing", nonetheless contains great depth and insight in its writing, acting and directing that says a great deal about both the strength AND the frailty of us human-folk. LR