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HBO's new film about Alfred Hitchcock's relationship with actress Tippi Hedren exudes the same intensity as the movie that it's about. Titled The Girl, Sienna Miller, 30, takes on the role of Hedren while Hitchcock is played by Toby Jones.

The story centers around the filming of the 1963 thriller The Birds, and spotlights the unhealthy relationship between the director and the blonde actress.

Jones, 46, says that Hitchcock became obsessed with Hedren and insisted she was the only one right for the role in Birds. "He knew every single aspect of film making, and I think he thought, 'Well, I’ll just make her into a good enough actress,'" Jones said of the master of suspense (via TVline), adding that Hitchcock probably thought, "[Hedren] has limitations as an actress, but I'm so able and so practical that I will be able to transform her to my needs."

The Girl, also starring Imelda Staunton as Hitchcock's wife Alma, will premiere on HBO Oct. 20.