Janet McTeer will play Maggie Smith's role of Professor McGonagall (Getty/Warner Bros) The deputy Hogwarts headmistress and head of Gryffindor House was portrayed by the late Maggie Smith.

Maggie Smith portrayed head of Gryffindor House and transfiguration teacher Minerva McGonagal in the films (pictured above in ‘The Sorcerer’s Stone’), and Janet McTeer will play her in the show.