I wouldn't have known this had I not just seen the movie, but it sounds to me like he was talking about the Witch in the old story Beowulf ("You've tamed every beast in the sea" Beowulf was known for fighting sea monsters), she would seduce people, she sometimes would appear like a snake, and she lived in the water:
"I watched you sink it to the depths of your lake
I knew the danger
But I still said your name"
"I know who started fires in this country" Her son Grendel would terrorize and start fires.
I wouldn't have known this had I not just seen the movie, but it sounds to me like he was talking about the Witch in the old story Beowulf ("You've tamed every beast in the sea" Beowulf was known for fighting sea monsters), she would seduce people, she sometimes would appear like a snake, and she lived in the water:
"I watched you sink it to the depths of your lake I knew the danger But I still said your name"
"I know who started fires in this country" Her son Grendel would terrorize and start fires.