Ending her character on the show has been done in a sad-but-clever manner according to Capaldi, who spoke on the UK’s Radio 1 Breakfast Show Wednesday morning. “It’s not quite what you think is gonna happen,” Capaldi told host Nick Grimshaw. “You think what’s gonna happen is gonna happen and then something else happens… It’s always clever the way these things are done on Doctor Who, so get lots of hankies ready. It’s sad over a number of weeks.
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Additionally, showrunner Stephen Moffat said in an interview with Movie Player, “Clara is gone and will never return… I can only say that what will happen will shock, surprise and terrify. Strictly in that order.”
http://editorial.rottentomatoes.com/article/peter-capaldi-says-get-your-hankies-ready/