Men with Steel Faces aka Radio Ranch

Singing cowboy Gene Autry's life at Radio Ranch is disrupted by attacks from the 'Thunder Riders,' soldiers from Murania, a futuristic, hidden underground kingdom. When scientists plot to exploit the city's radium and its Queen sees the surface world as a threat, Gene is drawn into the conflict. He must navigate the advanced subterranean city, rescue his friends, and stop a war between two worlds, blending classic western action with sci - fi spectacle. AKA Radio Ranch.