Krull

An indescribable monster and its army attack the planet Krull. In order to stop the invaders, two hostile nations decide to join their forces by the marriage of Princess Lyssa and Prince Colwyn. During the ceremony, the Slayers attack the palace, kill both kings, wound Colwyn and kidnap Lyssa. The next morning, the wise Ynyr seeks and finds Colwyn. With Ynyr's help, Colwn gains possession of a magic weapon, a five bladed sword, and together they go on their quest for the indescribable monster's black fortress to free Lyssa.