Under the Radar DVD of the Week: 'Big Box of Cowboys, Aliens, Robots and Death Rays'

This week, the oddest DVD to appear on release lists is:

“Big Box of Cowboys, Aliens, Robots & Death Rays”

In advance of the much-anticipated “Cowboys & Aliens” later this month, it’s a good time to look back on several old Hollywood chestnuts that mixed horse opera conventions with eerie sci-fi elements. They’re collected on the four-disc “Big Box of Cowboys, Aliens, Robots & Death Rays,” due out Tuesday.

The box set includes eight westerns containing elements of sci-fi, horror, robots, death rays and mystery that were produced in the 1930s and ’40s and featured such cowboy stalwarts as Gene Autry, Tim McCoy and Ken Maynard.

Here’s the roster:

“Radio Ranch” (1940). In this re-edited feature version of the serial “The Phantom Empire” (1935), singer-cowboy Gene Autry discovers a race of advanced humans living beneath the earth.

“Ghost Patrol” (1936). A professor invents a radium tube that makes internal combustion engines stop running. He and his invention are captured by a gang of robbers, and federal agent Tim McCoy is sent to rescue him.

“Tombstone Canyon” (1932). Cowpoke Ken Maynard hears the cry of the weird masked “phantom” of Tombstone Canyon. When Maynard discovers a man with a key to his past has been murdered by the phantom, he investigates.

“Riders of the Whistling Skull” (1937). In this supernatural western, the Three Mesquiteers (Robert Livingston, Ray Corrigan and Max Terhune) accompany an archeological expedition to a lost Indian city of gold called Lukachuke.