All 13 episodes from the fourth series of the rebooted CBBC show based on the children's books by Jill Murphy. Ordinary schoolgirl Mildred Hubble (Lydia Page)'s life is changed forever when a girl comes crashing into her home and tells her about Cackle Academy, a school for budding young witches. Despite having no magical background, Mildred is accepted into Cackle Academy and causes all manner of chaos as she struggles to perform her spells correctly. In this series, Mildred undergoes a radical transformation when an experiment goes wrong, but could this be the mischievous work of Ethel (Jenny Richardson) in the competition for head girl? The episodes are: 'The Three Impossibilities', 'Gertrude the Great', 'Happy Birthday, Indigo Moon', 'Enid Nightshade, Superstar', 'The Forbidden Tree', 'Maud's Magical Make-over', 'The Crystal Lake', 'Enid's Last Race', 'Mildred the Detective', 'A Witch in Time', 'Grounded', 'The Witching Hour: Part 1' and 'The Witching Hour: Part 2'.