Grendel retreats to his cave and with his final breaths, he tells his mother (Angelina Jolie), what has happened to him and she swears revenge. She travels to Heorot and butchers Beowulf's soldiers while they sleep. Hrothgar informs Beowulf and Wiglaf, who were not sleeping in the hall when the attack took place, that this was the work of Grendel's mother; she is the last surviving member of the Water Demons, long thought to have left the land forever. The two travel to Grendel's cave to slay her. When Beowulf encounters her, she takes on the form of a beautiful young woman. She promises to make him the greatest king who has ever lived, in exchange for the drinking horn and a son who will replace Grendel.