In an antediluvian world, Keltos warrior Rogan emerges as the lone survivor of a battle. Slaying a Nephilim giant from Shynar, Rogan takes back the mammoth his folk gifted the kings.

Soon, warriors are sent to recapture the mammoth and bring it to the Lord of the world, Zazaeil, a demon in human flesh, and the Nephilim giant Marduk, in the fabled city of Irem.

After learning that his sister is to be a sacrificial bride to Marduk, Rogan journeys to Irem in the company of Elisa, a warrior herself, whose mother is a wizardess. With a horde of warriors in pursuit, they encounter many evils, monsters, and challenges to their selves and souls.

Will the song of Rogan's blood make him strong enough to be the Killer of Giants?