Evanna Lynch
(Luna Lovegood)
Imelda Staunton
(Dolores Umbridge)
Natalia Tena
(Nymphadora Tonks)
Helen McCrory
(Bellatrix Lestrange)
George Harris
(Kingsley Shacklebolt)
Kathryn Hunter
(Mrs. Figg)
Please note that if the guy playing Shacklebolt looks familiar, it's because he was Katanga, captain of the Bantu Wind in Raiders of the Lost Ark.