 In the TV series her name is given as Imogen Drill and is notable as the only member of staff who is non-magical.In the episode "Power Drill" Mildred, Maud, and Enid feel sorry for Miss Drill and give her temporary magical powers, which, unfortunately become more permanent than they intended, resulting in Miss Drill becoming an actual witch and being more strict than usual.She also renames herself "Hillary Hemlock" (it seems that witches can change their names if they want to, as it is revealed in the episode "The Inspector Calls" that Mistress Hecketty Broomhead's real name is "Whilhelmina Wormwood").