This Merlin in der BBC foto contains
haube, oberbekleidung, überkleidung, overclothes, and sweatshirt.
There might also be
overgarment, oberbekleidung, gewand, box mantel, kastenmantel, box-mantel, sonnenuntergang sonnenaufgang, sonnenuntergang, and sonnenaufgang.
STORY: The song is about King Arthur's son Mordred, who was born between Arthur and his half-sister, Morgaine Le Fay. It's Morgaine Singen to him; persuading him to kill his father, which he ends up doing. Basically that is the story