With the news that Billie Piper was departing the show at the end of Series 2, the BBC knew they had to let her go out with a bang. Instead of killing the character off, she was trapped in a parallel dimension instead, which allowed her to make several subsequent random returns. The Tenth Doctor went as far as burning up a sun to say goodbye to her and she admitted that she loved him before their time ran out. The Doctor's mouth was open, forming the word "I", in what was seemingly going to be the first time in the show's history that he was going to confess his love for another...