The "unseen guardians" of the title are the Postal Inspection Service, which investigates mail order racketeering; the Underwriters' Laboratories, which are shown testing electrical equipment, fire extinguishers, and large floor safes; and those who run orphanages, who assure that the children in their care are placed in proper adoptive homes.

A young woman's murder sheds light on a crooked talent agency.

Two bit hood Eddie Condon (Kane Richmond) sells babies under the counter. A highly lucrative racket he soon finds out. But when will the police get wise to this highly immoral scheme of his? And will they be able to pin a rap on him before he goes a little too far? ALL IS TOLD in this EXCITING tale of CRIME and CORRUPTION!

Reporter Steve Haines, on the trail of a business tycoon, follows his subject onto an ocean liner and gets wound up in a cruise full of intrigue, romance and murder.

During World War II, an American bomber pilot is rescued after drifting at sea aboard a raft. After being administered truth serum, he tells the doctor a story of how he and the three survivors of his plane crash washed up on an island that was inhabited by a tribe of beautiful primitive cave-women, dinosaurs and a group of savage cavemen who are bent on abducting the women for breeding purposes.

1945 film by Phil Karlson

A man who has been framed on a murder charge is placed in the custody of a crooked U.S. marshal, who is secretly running a murderous claim-jumping gang.