Susan Irvine, commonly called Miss Irvine, is an evil witch and the secretary and right-hand woman of the Grand High Witch, the evilest woman in creation, who is masquerading as Evangeline or Eva Ernst.
Miss Irvine accompanies her employer to the hotel for the witch convention and is always at her side to implement her orders.
Miss Irvine is present during the meeting of the witches and helps the Grand High Witch removing her mask, while she removes her wig, revealing her horrific appearance. Susan also shows her real form with bald head, purple eyes and claw-like fingers.
Near the end, Miss Irvine is forbidden from attending to a witch banquet by Eva who told her that she is here to work and not to have fun. The mistreatment angers Susan, who turns on her employer. In the hotel room she makes herself a little banquet and says to herself that she never wanted to be one of the witches. She later goes down to the restaurant just to see the turmoil made by the witches turned into mice and the employees trying to kill them and is shocked.
After the Grand High Witch is defeated, Miss Irvine seems to be pleased to see what happened to other witches. The day when Luke and his grandma should leave the hotel, Luke gives Susan his home adress in the United Kingdom. Susan smiles as they leave and decides to turn away from her wicked ways and become a good witch. She travels to Luke's house and reverses his state of being a mouse, returning him to his normal human form as well as giving him his glasses and mice back. As she's leaving, she reveals to them that she now has real hair and no longer needs gloves as she has normal hands instead of claws. She then leaves to repeat the same process on Bruno.
Like her boss, Miss Irvine seems to despise children and wishes to cause them harm. Unlike other witches, Susan seems to be disgusted with their behavior when they turn Luke into a mouse and when she was rejected by Grand High Witch in attending the banquet, she told herself that she never wanted to be one of them. Also, after turning over to the side of good she displays a much happier and lighter personality, giggling as she casts her spells.
Susan Irvine in the hotel's reception.
Susan Irvine next to Grand High Witch.
Susan Irvine with Grand High Witch and Nicola Cuttle at the official witch business over tea
Susan helping Grand High Witch with removing her mask.
Susan Irvine observing the situation.
Susan Irvine in her real form.
Susan Irvine holding the Formula 86 in her hand.
Susan Irvine sitting alone in the hotel room.
Susan Irvine shocked to see the turmoil in the restaurant.