 That's one of my four favorites, with probably the best cliffhanger chapter, chapter five, when he's trapped in the Harrison mine by the Scorpion. My three other favorites were the second Commando Cody serial, which actually had Leonard Nimoy as a Martian zombie in chapter 11 in an underwater cave scene. Was that Radar Men on the Moon, or is that a different one? No, no, that's the first one. That's Radar Men from the Moon. That was Zeredik the Moon Menace.