Kelly Macdonald Joins 'Goodbye Christopher Robin' (Exclusive)

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Domhnall Gleeson will star as children's author A. A. Milne, whose son served as the inspiration for the 'Winnie the Pooh' character Christopher Robin.

Boardwalk Empire star Kelly Macdonald has joined Goodbye Christopher Robin, the film about children's author A. A. Milne.

Macdonald joins Domhnall Gleeson, who will play the famed author. The story centers on Milne's relationship with his son Christopher Robin, whose toys inspired the magical characters in Winnie the Pooh.

Margot Robbie is attached to play Christopher Robin's mother, Daphne, while Macdonald will play his nanny, Olive. The story sees the family swept up in the international success of the books, the tales bringing hope and comfort to England after WWI.

Simon Curtis (Woman in Gold, My Week With Marilyn) is directing the biopic from a script by Frank Cottrell Boyce and Simon Vaughan. Damian Jones and Steve Christian are producing. Fox Searchlight is handling the project through its deal with Jones. Searchlight's David Greenbaum, Matthew Greenfield and Katie Goodson-Thomas are overseeing.

Scottish actress Macdonald starred in HBO’s series Boardwalk Empire opposite Steve Buscemi. She also voiced the lead character Merida in Pixar’s animated film Brave, and was seen in Netflix’s recent comedy Special Correspondents, written and directed by Ricky Gervais. She's repped by ICM Partners and Independent Talent Group in the UK.