The battle between the knight Beowulf and the monster Grendel, famous from the epic 8th century poem, is updated in this sci-fi animation adventure. In a quarantined outpost somewhere in the post-apocalyptic future, a monster comes each night to devour those imprisoned there. Nobody is ever able to confront the monster, that is, not until the mysterious wanderer Beowulf arrives. Beowulf fights the monster, injures it, and gives new hope to those who dwell at the outpost. But who is he? Why do his wounds heal so quickly? What is his dark secret?