Beowulf gets to the lake to take on Grendels Mother. He then leaps in and sinks to the bottom. He bought his men along as well as his sward, and his helmet.
During this scene, Beowulf is being dragged and bullied into a tunnel by Grendles mom, She then finds out that she cannot get ahold of his skin due to his clothing. He then tries to stab her and after the failed attempt, he then fights her with his bare hands
Beowulf wins the battle against his mother. After coming up from the bottom, everyone runs because they don't think it is Beowulf. Shortly after, Beowulf has her head and he is a clear champion