Who is Mrs Flood in Doctor Who? All the theories around mystery Anita Dobson character

While most of the finale was taken up with questions surrounding Sutekh's return and Ruby Sunday's origins, there were also some pieces added into the puzzle of another character - Anita Dobson's mysterious Mrs Flood.

Mrs Flood is the next-door neighbour of Ruby Sunday and her family, and seems like a sweet and innocuous lady - until the credits scene of the Christmas special The Church on Ruby Road, when she turned to the camera and said: "Never seen a TARDIS before?"

We then got a smile and a wink from the mysterious Mrs Flood to roll into the rest of the credits and ever since then it's clear there is a lot more than what meets the eye.

Speaking on Doctor Who: Unleashed at Christmas, showrunner Davies said: "Mrs Flood is a mysterious character. You will eventually find out more about her. She’s a slow burn, Mrs Flood. Who is Mrs Flood? Come back and find out!"

Dobson, meanwhile, added: "Today what you see is a friendly neighbour. What the future may be, no one knows. Russell is writing it as we speak."

So, just who is Mrs Flood? RadioTimes.com has round-up all the theories about the mystery character.

Who is Mrs Flood in Doctor Who? All the theories for Anita Dobson role

Susan Foreman?

Considering Mrs Flood's familiarity with the TARDIS and numerous references to the Doctor's family, offspring and a namecheck for Susan herself, some fans have speculated that Mrs Flood is indeed the Doctor's long-lost granddaughter Susan Foreman, played by Carole Ann Ford.

Of course, Susan has a long history with the TARDIS, and also knows all about time travel - could she have somehow gone back in time and at some point also have experienced a regeneration?

• Read More: Doctor Who's Carole Ann Ford hints at Susan's return after The Devil's Chord

A member of the Pantheon?

Of course, it was teased back in Wild Blue Yonder that dangerous forces would be on their way, and so they were with the likes of the Toymaker (Neil Patrick Harris) and Maestro (Jinkx Monsoon), but we know more are on the way, as teased by Russell T Davies.

Could Mrs Flood be another member of these powerful beings, and could she be keeping an eye on Ruby Sunday for a reason?

Maestro was also the only other character apart from the Doctor to break the fourth wall in recent episodes...

Another Time Lord?

Of course, Susan is not the only Gallifreyan to potentially take the form of Mrs Flood. Whether it is the Master, the Rani, Romana or the Meddling Monk - multiple people could now appear to be Ruby's sweet neighbour.

It would certainly explain the familiarity with a TARDIS, that is for sure!

• Read More: Doctor Who showrunner confirms the Master is "parked": "Time to start again"

Ruby Sunday's mother?

There was a theory that Mrs Flood could be the mysterious biological mother of Ruby Sunday.

However, in Empire of Death that was revealed not to be the case, so unless she is in some other way related to Ruby, this feels like one theory we can scratch off the list.

An older Ruby Sunday?

Given the timey-wimey nature of Doctor Who, could she even be an older Ruby Sunday?!

It would be a strange twist, but also totally Doctor Who.

Something entirely unexpected?

Given how little evidence we have to go on with Mrs Flood, there really is no limit to explaining her true nature.

In The Legend of Ruby Sunday, Mrs. Flood made another appearance, summoned by Carla Sunday (Michelle Greenidge) to look after her mother Cherry (Angela Wynter) so that Carla can accompany Ruby (Millie Gibson) to UNIT HQ.

But Mrs. Flood was far from a perfect caregiver – rather than make Cherry a cup of tea, she delivers an ominous warning. "I'd be very careful, Mrs Sunday – there's a storm coming in… He waits no more."

Clearly, Mrs. Flood was somehow aware of the imminent arrival of the god-like being Sutekh – but just how she knows this, and who she really is, remains to be seen.

In Empire of Death, Mrs Flood asked Cherry Sunday whether she believes in the power of prayer. When she said that she does, Mrs Flood added: "Then tell your maker I will come to storm down his gates of gold and seize his kingdom in my true name."

Cherry asked who she was, but no answer was forthcoming. As the pair were later consumed by Sutekh’s dust of death, Mrs Flood told Cherry: "I’m sorry, you tiny little woman, I’m so so sorry, it ends like this… I had such plans."

They were later both restored at the end of the episode, along with all other life in the universe, and Mrs Flood called the Doctor a "clever boy".

However, perhaps the biggest teaser this season as to Mrs Flood's identity came in the final scenes of the episode, where Mrs Flood was seen on the roof of Ruby’s building, dressed in a fur coat and holding an umbrella to shield her from the snow.

She broke the fourth wall for the second time, speaking to the camera and saying: "And that's how the story of The Church on Ruby Road comes to an end. With a very happy ending for little Ruby Sunday.

"But life goes on, doesn't it? Ruthlessly. And what happens, you might wonder. Oh, what happens to that mysterious traveller in time and space known as the Doctor? I'm sorry to say his story ends in absolute terror. Night night!"

Could Mrs Flood be a returning character, or is she something completely new and unpredictable? Rest assured we will keep our eyes peeled for every clue possible.

Read more:

• Doctor Who hints at Susan’s return – and confirms major family reveal
• Doctor Who's Bonnie Langford explains UNIT "comedy duo" energy with Yasmin Finney

Doctor Who returns this Christmas on BBC iPlayer and BBC One. Previous seasons are available to stream on BBC iPlayer.

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