Doctor Who Christmas special synopsis promises "enchanted glass people" - and the voice of a Torchwood actor

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Well now the BBC has revealed the official synopsis and it's very similar – except for one key difference...

What's not mentioned in the DVD version is that the adventure will see the Doctor and co meeting "enchanted glass people, stealing their victims from frozen time", which you have to say sounds like a pretty significant omission...

We've already seen one of these frozen moments in the trailer for the episode when Mark Gatiss's character The Captain and fellow Doctor Who writer Toby Whithouse's German soldier are shown trapped in a single moment on a First World War battlefield – and we know from a scene released during Children In Need that the Captain is among those "being pursued by an alien through frozen time".

What we don't know is who these mysterious "glass people" are – well, except for one of them...

Because we've also been told that a character known as the Glass Woman will be voiced by Nikki Amuka-Bird – and this is not her first foray into the Doctor Who universe.

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Amuka-Bird was seen most recently in contemporary drama NW, but back in 2008 she had a role in a series-two Torchwood episode as an alien sleeper agent.

Always nice to see a familiar face return to Doctor Who – even if, in this case, she's just a voice...

Here's the full synopsis for Doctor Who: Twice Upon a Time...

"Two Doctors stranded in an Arctic snowscape, refusing to face regeneration. Enchanted glass people, stealing their victims from frozen time. And a World War One captain destined to die on the battlefield, but taken from the trenches to play his part in the Doctor's story.

"An uplifting new tale about the power of hope in humanity’s darkest hours, Twice Upon A Time marks the end of an era. But as the Doctor must face his past to decide his future, his journey is only just beginning..."

And here's a rather nice 3D video version of the new promotional image...