Five British soldiers are sent to a detention camp in the Libyan Desert, including Sergeant Major Roberts (Sean Connery), whose conviction for the assault of an officer is shrouded in mystery. As punishment, the vicious Staff Sergeant Williams (Ian Hendry) orders the prisoners to continuously climb a man-made hill in the scorching desert heat. Though his colleague, Staff Sergeant Harris (Ian Bannen), sympathizes with the new detainees, he can only watch as Williams goes to sadistic extremes.