Susan Twist makes chilling reappearance in new Doctor Who preview

In a new teaser of the forthcoming episode, the Doctor can be seen talking to Kate Lethbridge-Stewart and other members of UNIT, explaining that everywhere he lands, "a woman appears".

Zapping through each of her forms, the Doctor says: "Look. So she is a comms officer in the planet Pacifico del Rio. She's someone's mum in Finetime. She's an ambulance. She's a portrait in 1813, and the list goes on."

However, it becomes apparent everyone is aware of this woman's many forms but the Doctor, as Lenny Rush's character, Morris, reveals who she is in present day.

A woman appears on screen giving a speech, saying: "This is when it changes. This is when the whole word is changed, by me!"

It was previously confirmed that the Doctor would be coming face-to-face with a new character, Susan Triad.

In a first look image of The Legend of Ruby Sunday, Susan Triad could be seen making a presentation of S Triad technology, while another image sees her shaking hands with Ncuti Gatwa's Doctor. But who is she? Saturday 15th June could very well be when fans find out.

The synopsis for The Legend of Ruby Sunday reads: "The Doctor and UNIT investigate Ruby's past. But as the Time Window reveals horrifying secrets from Christmas Eve, the mysterious Triad Technology unleash the greatest evil of all."

While showrunner Russell T Davies has remained somewhat tight-lipped on the key plots of the finale, he teased that fans "will be screaming" as they watch the episode.

He said: "I have to say, we are dropping these episodes at midnight, and if ever you’re going to stay up until midnight with a bottle of cider or a box of chocolates and sit there and watch Doctor Who, I would recommend it for that one – because you will be screaming."

Doctor Who continues on Saturday 15th June on BBC iPlayer and BBC One. Previous seasons are available to stream on BBC iPlayer with episodes of the classic series also available on BritBox – you can sign up for a 7-day free trial here.

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