Prisoners of the Lost Universe

Three people are transported into a parallel reality, where they find they must use modern technology, but medieval weapons, in order to save the citizenry from a murderous warlord.

Prisoners of the Lost Universe is a 1983 adventure fantasy movie directed by Terry Marcel, starring John Saxon, Richard Hatch, Kay Lenz. It holds an IMDb rating of 3.8/10 from 2,314 votes and runs 1h 34m.