Companions Amy Pond and Rory to leave Doctor Who

Steven Moffat reveals massive spoiler at screening attended by George Osborne and Ed Balls

LAST UPDATED AT 09:42 ON Fri 16 Dec 2011

DOCTOR WHO companions Amy Pond and Rory - played by Karen Gillan and Arthur Darvill - face a "heartbreaking end" during Series 7 of the BBC's blockbuster sci-fi show.

Executive producer Steven Moffat announced the massive spoiler at a screening yesterday of the Doctor Who Christmas special, The Doctor, The Widow and The Wardrobe, which was attended by the Chancellor, George Osborne and the Shadow Chancellor Ed Balls.

"The final days of the Ponds are coming," said Moffat. "I'm not telling you when or how, but that story is going to come to a heartbreaking end."

A new companion will join the Doctor, Matt Smith, at some point in the next series, but the actor's identity is unknown - and it is thought the role might not yet have been cast.

As the title suggests, the Christmas episode borrows heavily from C.S. Lewis's children's classic, The Lion, the Witch and the Wardrobe. Clare Skinner plays a Second World War widow whose children are evacuated from London to Dorset. Bill Bailey and Arabella Weir also make fleeting appearances.

The episode received a warm welcome at yesterday's screening. Hiding his disappointment that a room full of journalists, asked their favourite monsters, avoided the temptation to mention either Osborne or Balls, Den of Geek's Simon Brew wrote: "It's very, very funny... for me, the best Christmas special since The Christmas Invasion (and I say that having loved last year's, too)." ·