Kate Duchêne born Catherine Anne Purves Duchêne (January 5, 1959) is a British actress. Duchéne is best known for her work as Miss Constance Hardbroom, the strict Deputy Head and Potions Teacher on the popular TV series The Worst Witch. Having stayed with the programme for its three-year run, and appearing in the first episode of its 2001 spinoff Weirdsister College, "The All Seeing Eye", Duchêne disappointed many fans by failing to return for the second spinoff, The New Worst Witch (2005–2006).