8 Doctor Who Actors Who Were Fired Or Quit
2. Billie Piper
Billie Piper had one of the most important roles in Doctor Who history, having been given the job of playing the new Doctor's first companion when the 2005 series began. She showed up as Rose Tyler opposite Christopher Eccleston, and after he left the series, David Tennant and she connected perfectly on screen.
Both Tennant and Piper were very well received by the fans, and more than a few million "shipped" the two characters. Of course, their time together wouldn't last forever, and in a seriously heartbreaking conclusion, they were separated across dimensions in a tearjerker of an episode that saw them say goodbye.
Rose's departure came from Piper's desire to leave the show. She became overwhelmed at how much Doctor Who had completely taken over her life. The demand on her time as well as fan speculation about what might happen next exhausted her to no end.
As a result, she asked to be written off the show, so after one season with the 9th and one season with the 10th Doctor, Rose Tyler's time in the TARDIS was at an end. She returned in a guest spot in season four to close out her character fully, but after that, she was done.