Mortimer will play Jane Banks, who along with her brother Michael (who will be played by Ben Whishaw in the pic), was one of the children the magical titular nanny looked after in the original 1964 film, and is now all-grown-up in this installment. The movie is set 25 years after the original.
The movie also stars Meryl Streep as a cousin of Poppins’. Blunt will be playing the title character, with “Hamilton” star Miranda playing a street lamplighter named Jack.
The film will be directed by Rob Marshall and produced by Marshall, John DeLuca, and Marc Platt.
The screenplay will be written by Oscar nominee David Magee and is based on “The Mary Poppins Stories” by P.L. Travers, with Marc Shaiman composing an all-new score. Scott Wittman will be writing original songs.
The film is set to bow on Dec. 25, 2018.
In the past couple of years, Mortimer has starred in two HBO shows, “The Newsroom” and “Doll & Em,” and can be seen next in the CBS Films movie “The Sense of an Ending” and Legendary’s “Spectral.” She is repped by WME and Lighthouse Management and Media.