Rose Byrne has signed on to star as Moira MacTaggert, the Scottish geneticist who's also a love interest for Charles Xavier (James McAvoy), while Jason Flemyng will play Azazel, the mutant who would eventually be the father to Nightcrawler.
MacTaggert, if you'll remember, was actually seen in X-MEN 3 in a post-credits sequence and was played by Olivia Williams. With Mystique already cast in the film, it certainly seems that we'll see the genesis of Nightcrawler with both his mother and father cast in this film. I wouldn't expect him to be a huge part of this film but probably someone at an early point of Mystique's storyline.
Rose is currently filming the Kristen Wiig comedy BRIDESMAIDS and can be seen next in the James Wan horror film INSIDIOUS.
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