A group of Nazi survivors save Hitler's brain keeping it alive in a huge jar hooked up to a machine. The Nazis plan to release a deadly gas destroying all life on the planet. To ensure their success they kidnap Professor Coleman the only man on the planet with the antidote to the poison gas.

A Canadian mountie is framed for committing crimes, while investigating a gang of criminals.

A 12 episode serial starring Rex, the King of the Wild Horses and Rin-Tin-Tin, Jr. Rex is brought from the island of Sujan, where he is worshiped as a God-Horse, to the U.S. to be trained as a polo pony. He escapes, meets Rinty and with the help of Frank Bradley is returned to Sujan. The natives have been persuaded to turn against their God-Horse, however he is rescued just in time before he is burned as a sacrifice.

While the original title, "Trailing the Killer" isn't a misnomer, it was a bit misleading since the "trailer" is a dog named Caesar Caesar the Dog) and the killer is a mountain lion, aka as a cougar or puma the narrator was quick to point out. But the makers also pointed out that Caesar "is the most intelligent dog actor since Rin-Tin-Tin" which probably lured a few Rin-Tin-Tin fans with a show-me attitude. Caesar prowls around the woods of the Northwest, dispatches a rattlesnake, visits his she-wolf mate and their pups, pauses to watch the dainty habits of a raccoon personally washing every morsel of food before eating it---and that raccoon had enough food to use up several minutes of running time---and then saves sheepherder Pierre (Francis McDonald)) from getting et up by one mean mountain lion. Rin-Tin-Tin he ain't, but then who was? Commonwealth...