After Beowulf had killed Grendel, the monster that was hunting Heorot, he had to fight another one; Grendel’s mother who is seeking revenge. As soon as Hrothgar explains his concerns to Beowulf, the hero accepts the challenge.
After talking to the king, Beowulf goes with his men to the boiling, bubbling, and scary lake to kill Grendel’s mother. The lake is filled with boiling water and surrounded by monsters.
Beowulf gets in the water, Grendel's mother takes him by the arm and drag him to the bottom of the lake, where he notices that the boiling water can't hurt him.
In the battle arena, Grendel’s body is nearby. During the fight, Beowulf is about to give up until he sees a light that leads to a giant’s sword.
He takes the sword and kills the water witch.
Beowulf returns to Heorot with the green trophy in one hand, to prove his victory.