Einar (Kirk Douglas) is a Viking prince, son of Ragnar (Ernest Borgnine), the Viking King. Eric (Tony Curtis) is a Viking slave and the illegitimate son of Ragnar. Only the King and the slave know this secret. In public, Eric and Einar are bitter enemies. Eric’s falcon is responsible for the horrible scar on Einar’s face. Einar punishes Eric by having him tied down in a pool of crabs, but he survived to continue the feud with his bother. In one sea raid, Einar and his men capture an English princess, Morgana (Janet Leigh). Einar thinks he will become Morgana’s husband, but she has fallen in love with Eric, one of two conflicts pitting brother against brother. The other conflict to be fought is over who will control the British throne.