It's easy to see why Jenna Coleman signed up for another full series of Doctor Who. Series 8 offered up Clara some meaty storylines and allowed Coleman to deliver some outstanding powerhouse performances. She may have been fun with Matt Smith but with Peter Capaldi she delivered a Doctor/companion partnership to rival the Fourth Doctor and Sarah Jane. However, if Doctor Who has taught us one thing then it's that nothing lasts forever. Doctor Who thrives because it is able to continually reinvent itself with new main characters every year or couple of years. Fans are all hoping Capaldi is in this for the long run which means Coleman should leave after 2015 if the show is to remain fresh and exciting. Given the trauma of Series 8, the hope is that it will ultimately be a happy ending for Clara - perhaps leaving the Doctor to travel the stars? Either way, as good as Clara is, when she leaves it needs to be for good this time.