Unexpectedly, news has broken that one of the key roles in Game of Thrones has been recast. Jennifer Ehle had been tapped to play the role of Catelyn Stark, the wife of Lord Eddard Stark and a major protagonist in the series, and played the role in the pilot episode. Following the series being picked up for a ten-episode full season, it has now been confirmed that Irish actress Michelle Fairley will be replacing her.

The news was somewhat unexpected. Ehle, the star of the mid-1990s (and possibly definitive) BBC mini-series version of Pride and Prejudice and a very respected stage actress, was one of the higher-profile castings for the pilot and her casting was considered a coup, along with that of Sean Bean and Peter Dinklage. No official reason has been given for Ehle's withdrawal from the project, but it is apparently more of an issue about clashing schedules rather than any concerns with her performance.

46-year-old Michelle Fairley is much more a veteran of episodic, ongoing television than Ehle, and recently gained positive notices and reviews for her portrayal of footballer George Best's alcoholic mother in a recent and acclaimed BBC TV movie. She is currently filming the role of Hermione's mother for the final two Harry Potter movies. Westeros.org has some more information on her here.

Obviously, disappointing news. I thought Jennifer Ehle was an excellent match for the role of Catelyn. On the other hand, Michelle Fairley handled some very challenging material in Best: His Mother's Son and looks like she could be a good fit for the role.

It is unclear how big an impact on production this recasting will have. Ehle had already filmed her scenes in the first episode, including the big feast scene and the arrival of King Robert and his entourage at Winterfell. Reshooting these scenes could involve major expense. It'll be interesting to see how HBO handle this situation.