Candidates 11 to 22
11.
Alex KingstonAlex was cast in the 2008 episode, Silence In The Library, as Professor River Song - speculated to be a future companion / girlfriend / wife of the Doctor.
The professor is another of Stephen Moffat's characters. The writer said at the time: "This character is destined to play a major role in the Doctor's future." As his next companion, perhaps?

12.
Bernard CribbinsBernard first appeared in the 2007 Christmas special, Voyage Of The Damned, and was later revealed to be Donna Noble's grandfather, Wilf.
When the Doctor left Donna with her memory wiped, Wilf promised to look up at the sky every night and remember him on Donna's behalf. He's set to join the Doctor for a trip in the Tardis in 2009, but could this be the beginning of a beautiful friendship?

13.
Catherine TateWhen we last left Donna, her memory had been wiped with a dire warning from the Doctor that if she were to remember her travels with him it would mean her death. It has been confirmed, however that Catherine has been lined up for a comeback in 2009.
A show source said: "Anything can happen in Doctor Who. His assistants are always recurring and Donna is no exception. When you're a Time Lord you can go back to any point in history and meet whoever you want." Maybe there's hope for Donna yet.

14.
Catherine Zeta JonesRussell T. Davies has revealed that if a Doctor Who movie were to be made, he'd want Welsh star Catherine Zeta-Jones to play The Doctor's assistant.
He said: "Being from Wales myself, I would love to have Catherine Zeta-Jones as a companion for The Doctor." Catherine hasn't commented.

15.
Dervla KirwanIrish actress Dervla appeared as Miss Hartigan in last year's Christmas special, The Next Doctor. That adventure, set in Victorian England, saw the return of the Cybermen and featured a new mutant Cyberman called Cybershade.
She could be one to watch.

16.
Patrick StewartPatrick Stewart has been confirmed as a guest star for one of 2009's specials. But the Star Trek actor won't be appearing as a companion.
A BBC source revealed: "Patrick's role is still being finalised but the plan is for him to play a renegade Time Lord called the Meddling Monk, who was last seen in Doctor Who in the 1960s. The Doctor thought his entire race was wiped out and gets a huge surprise to find another member of his species."

17.
JK Rowling!!!Russell T. Davies has revealed that JK "politely declined" the chance to write an episode, but also spoke about an episode idea in his book: "BAM! I thought, don't ask J.K. to write a Doctor Who, ask her to be in a Doctor Who! Imagine it. J.K.'s imagination becomes real! The Doctor arrives and has to battle through a world of witches and wizards."
It was not to be, however. Russell revealed that David Tennant vetoed the idea. Now that David's going could she be persuaded?

18.
Elisabeth SladenSince being a series regular in the 1970s, Elisabeth has returned on several occasions, most recently her character Sarah Jane Smith helped to destroy the Daleks in the season four finale.
But sadly Elisabeth feels that she won't return to the show. The actress told Doctor Who Magazine: "I said to David: 'I've never thought this before, but I think this is the last time I'll be here'. It felt like it was my last time on Doctor Who. I'm happy with that, you have to stop somewhere."

19.
John SimmLast seen refusing to regenerate and dying in the Doctor's arms, John Simm is set to reprise his role as the Master this year.
But how will he return? Could the figure fingering the Master’s ring after his funeral provide the key? Either way, we doubt the Doctor will be welcoming his arch enemy back into the Tardis with open arms.

20.
Rachel StevensStrictly Come Dancing contestant Rachel was pipped at the post for the part of Rose by Billie Piper when the Dr Who revival was originally cast. The singer has since said: "Things happen for a reason. If the right thing came around I'd love to do something."
Could Rachel be next to enter the Tardis?

21.
Jessica HynesJessica guest starred as the Doctor's girlfriend Joan Redfern in the 2007 episodes Human Nature and The Family of Blood. In an alternate future she became his wife, the mother of their two children, and grew old with him.
But sadly, the romance was not to be. The Doctor got his memory back, and Joan decided she was in love with the human Doctor, rather than the Time Lord. Might she change her mind?

22.
Noel ClarkeThe series four finale left open the possibility of Noel's character Mickey Smith going to work for Torchwood 3 during its third season, but there has been no indication that he'll appear.
Could he be returning to the Tardis instead?
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