It's an abrupt and embarrassing switch for a high-profile film. Fans of E L James' erotic best-seller are eagerly awaiting the movie adaptation, which will be directed by Sam Taylor-Johnson.
Dakota Johnson remains in the co-starring role of Anastasia Steele. A replacement will be sought for Hunnam, who last month said he initially turned down the role.
When his casting was announced in September, many vented online that the "Pacific Rim" actor was ill suited to play the seductive billionaire. Producers Dana Brunetti and Michael De Luca took to Twitter to defend the choice, maintaining their two leads had good chemistry together.
Representatives for Hunnam didn't immediately respond to a request for comment Saturday.
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