"Gunsmoke" clip: James Arness as Marshal Matt Dillon and Dennis Weaver as Chester face an evil photographer played by "Family Affair's" Mr. French, Sebastian Cabot

I found this interesting sequence in the "Gunsmoke" episode "The Photographer," which premiered April 6, 1957, during the long-running TV Western's second season. The above clip reveals significant plot details, so watch it and read this post only if you're OK with spoilers. The sequence takes place on the Upper Iverson.

"Gunsmoke"

Many people consider "Gunsmoke" to be the greatest Western TV series of all time, with the show setting a number of longevity records in its 20-season run on CBS, from 1955 to 1975. By the time the dust settled, the series had racked up a whopping total of 635 episodes — and a number of those episodes, especially in the early seasons, were filmed on the Iverson Movie Ranch.

Sebastian Cabot as Professor Jacoby on "Gunsmoke"

Joining the regulars for "The Photographer" was Sebastian Cabot, seen perched in a "Cheyenne burial tree" on the Upper Iverson in the above screen shot from the episode.

Sebastian Cabot as Mr. French on "Family Affair"

Cabot was already an accomplished film and TV actor at the time but still almost a decade away from what turned out to be his signature role as Mr. French, the gentleman's gentleman and reluctant nanny on "Family Affair."

In the Midway Oaks in "The Photographer": Matt and Chester get tied up

Cabot plays Professor Jacoby, an evil frontier photographer, in the "Gunsmoke" episode. In this shot he and his assistant Gart, played by Dean Fredericks, tie up Marshal Dillon and Chester to one of Iverson's Midway Oaks.

As Gart looks on, Jacoby sizes up his photo. Many of the trees that appear in this sequence may not have survived, but the rocks that can be seen in the background in this shot, which were found on the Upper Iverson's North Rim, remain in place today, surrounded by large residential estates.

The timely arrival of a Cheyenne hunting party foils Jacoby's plans — especially with the braves bent on avenging his desecration of their burial tree. In the background are some of the familiar rock features of the South Rim.

A few of the South Rim rocks are noted in this version of the shot, along with a portion of the Midway Oaks. You can read more about the Midway Oaks by clicking here. For background on Gold Raiders Rock, click here, and for Notch Rock, you can use the links in this sentence to see shots of the rock in a Tarzan movie, the TV show "Adventures of Superman" and the 1986 movie "The Tomb."

Still tied up and helpless to do anything about it, Dillon and Chester watch as the Cheyenne attack Jacoby and his assistant.

Jacoby sees he's about to meet his fate — on the receiving end of a Cheyenne tomahawk.

Freed from their bonds by the Cheyenne, Matt and Chester, in the background, set out to survey the carnage. The burial tree is still visible, to the left of Dillon.

The Cheyenne burial tree remains in the picture as Dillon and Chester approach the body of Jacoby.

This version of the shot pinpoints where the skull can be found in the burial tree, although it's difficult to make out in this photo. It's easier to spot in the next screen shot.

With the skull visible in the burial tree between the two men — just to the left of Chester, at eye level — Matt gets ready to wax philosophical, offering a few words of wisdom to bring the episode to its conclusion.