Morgan le Fay, Arthur's wicked half-sister, uses her magic to stir up trouble. She has The Green Knight presents a challenge: a brave man may strike an undefended axe blow at the Green Knight with the proviso that the brave man must accept a blow in return a year and a day later. Gawain excepts the challenge but to everyone’s shock, the Green Knight is not killed by the blow. In fact his severed head is still able to sing. The bargain struck, poor Gawain is condemned to set off for the snowy wastes of the North to keep his appointment with death.