The Secret Empire - Season 1 (1979)

U.S. Marshal Jim Donner learns that a gang of hooded desperadoes is stealing wagons of gold, but that knowledge nearly costs him his life when one of the outlaws shoots him in the back with an unusual weapon. After being treated by Millie Thomas, he and Billy Thomas head into the badlands to pick up the trail of the criminals. Billy discovers an unusual keyhole to which a key the marshal grabbed from one of the hooded goons fits. Once inside, the marshal discovers the missing gold, but accidentally enters an elevator which transports him into an advanced civilization ...

Attracted to the handsome Marshal Donner, Princess Tara orders him revived despite the emperor's decree that all outsiders be executed. Tara orders the Marshal and her lovely enemy Maya bound and brought to her chamber where the stolen gold is used to power the Positron, a brainwashing device that Maya has so far managed to defeat its effects. Using the silver metal in the marshal's badge, Maya manages to free herself and Donner and, using the brainwashing machine, forces the Princess to allow them to escape. Once in the cave outside, the Marshal is attacked by a huge...

After Maya rescues Jim Donner from the alien creature, she explains that her people fled from another planet do to its oppressive ruler. After establishing themselves in a underground city, Thorval and his minions overthrew her father's benign rule and enforce their will with the Compliatron which is powered by gold. Thorval's henchman capture Donner and try to force him to reveal why Maya and her friends are immune to the Compliatron's compelling force. When Donner refuses, he falls into a pit full of hungry alien creatures, taking Princess Tara with him by accident.