Decades before the beginning of the novel, the Witch caught a falling star which became her fire demon. Because of this, the Witch became evil. The relationship between her and her fire demon was parasitic, as the demon was draining her and her magic. Fifty years before the events of Howl's Moving Castle, the current King's father banished the Witch to the Waste, and the Witch bore the current King a grudge for that.
A year before the events in the novel, Wizard Howl pursued her, and later jilted her. Out of fury and the need of his head for her human puppet, the Witch cursed him so that he would be forced to return to the Waste.
She is a talented witch who was so beautiful that Howl pursued her, but after finding out that she used magic to keep herself looking young and beautiful, he left her. She is still in love with Howl however, and uses her magical powers and henchmen to try and capture him after seeing him with Sophie. That is why she arrives at night to Sophie's hat shop, and insults her before turning her into a 90 year-old woman. As Sophie leaves her hometown in order to break the curse on her, she reaches Howl's castle. Through Sophie's pocket, the Witch uses ancient sorcery to put a powerful spell on Howl in the form of a note. The scorch marks read:'You who swallowed a falling star, oh heartless man, your heart shall soon belong to me.'
Initially the antagonist, the Witch becomes somewhat of a protagonist after Madame Suliman lures her to the castle to drain her of her magical powers, restoring the Witch to her actual appearance and age, and replacing her as the antagonist in the movie. She is voiced by Lauren Bacall in the English dubbed version.