The big-screen adaptation of Maurice Sendak's children's classic will use a combination of real actors, computer animation and live-action puppeteering, The Hollywood Reporter said Monday.
The movie is slated for release next fall.
Ambrose, best-known for her work on TV's "Six Feet Under," will play KW, one of the giant creatures in the land of the Wild Things.
A production source told the trade paper the filmmakers liked Williams, but didn't think her voice matched their vision of how the beast should sound.
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