A prelude to 'The Name of the Doctor' will be available to watch following Neil Gaiman's 'Nightmare in Silver' on Saturday, May 11, according to the Radio Times.
The three-minute episode will see the Doctor (Matt Smith) and Clara (Jenna-Louise Coleman) speak directly to camera, as each considers how little they know about the other.
'The Name of the Doctor' promises to resolve the ongoing mystery surrounding Clara, while showrunner Steven Moffat has also claimed that the episode will "change the course of Who forever".
"It's full of surprises and questions that have never been answered in the history of Who, including the Doctor's greatest secret," said the sci-fi drama's head writer.
The finale prequel will be available to users of the red button service from 7.40pm to midnight, every evening up until 'The Name of the Doctor' airs on Saturday, May 18.
Doctor Who continues this Saturday at 6.30pm on BBC One with new episode 'The Crimson Horror'.
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