Prison Planet (1992)

In the year 2200 Earth is under the dictatorship of an evil king, with only a band of intrepid rebels to oppose him. Blaine, one of the rebels, gets himself arrested and sent to prison in search of the true ruler, the kings brother. But the prison is protected by a brutal warlord and his equally sadistic warriors, whom Blain must battle if he ever hopes to find truth and justice.