the worst witch is a british-canadian itv television series about a group of young witches at a school for magic. the series stars georgina sherrington and felicity jones, and is based on "the worst witch" books by jill murphy (published from 1974 onwards). it aired for a total of 40 episodes spread over three series between 1998 and 2001, before being followed by "weirdsister college." most episodes revolved around the school, following the adventures of mildred and her friends. the series was later followed by "the new worst witch", which ran for two series and chronicled the experiences of mildred's younger cousin hettie as she attended the school.