Rebecca Ferguson is in talks to star in the Roald Dahl biopic.
The 34-year-old actress is reportedly in negotiations to star as actress Patricia Neal alongside 'Downton Abbey' star Hugh Bonneville as the children's author in the new picture which will be co-produced by Atticus Pictures and Goldcrest Films.
Bonneville, 53, became a household name in the TV period drama and has since starred in a number of Hollywood movies including 'Paddington' and is reprising his role as Mr. Brown in the sequel.
Elliot Jenkins, of Atticus Pictures, told Variety: "Personally I can't imagine anyone better than Hugh Bonneville to give the ambivalent nature of Roald Dahl's life. He was such a man of wounded parts below his polished veneer of self-confidence."
The late Dahl is one of the world's most famous children's authors and created unforgettable novels including 'Charlie and the Chocolate Factory', 'The BFG' and 'James and the Giant Peach'.
The currently untitled biopic is set to look at the author's marriage to actress Neal and it will move between New York, England and Los Angeles in 1960s - a time when he struggled to write.
Neal was a renowned actress, who made her film debut in 1949 in 'John Loves Mary', and she went on to star in many Hollywood hits including 'Breakfast at Tiffany's' with Audrey Hepburn in 1961.
Although the project is currently untitled, the publication has described it as being similar to 'Saving Mr. Banks' and 'Finding Neverland' and based around Stephen Michael Shearer's biography of Neal, 'An Unquiet Life'.
The script is being written by John Hay and David Logan, who both worked together on the TV drama 'Lost Christmas'.
Pascal Degove, managing director of Goldcrest Films, said: "This film tracks the personal triumphs and tragedies behind the marriage of two globally known superstars.
"John and David's excellent script is an audience-pleasing portrayal of Roald and Patricia's touching love story, backgrounded by the cinematic sweep of the swinging 60s."