Doctor Who 50th anniversary will be a "nationwide celebration" with "lots of aliens and Daleks"

“There will be lots of aliens and Daleks and things like that – or maybe there won’t,” said Stephenson, of the 50th anniversary special, which is likely to screen in November, the month when the first ever episode aired.

“There’s many different things to take into account. We’ll also have a Christmas special after that and it all connects. Or maybe it doesn’t. There is lots to work out…"

One thing does seem clear – the on-screen anniversary celebrations will not be limited to a single special episode, with Stephenson saying he is keen to “make individual programmes more than the sum of their parts”.

“Ninety-nine per cent of the British public know about Doctor Who and so have a personal connection to it,” he said. “Most people have their own Doctor Who. [The plans are] drawing on the nostalgia to say something bigger. It's a nationwide celebration of both Doctor Who and the BBC because I think they are so synonymous."

Speaking at a BBC drama launch, Stephenson also revealed plans to broadcast the 50th anniversary special in 3D, on both TV and in cinemas. "It's very exciting and feels very innovative," he said.

Doctor Who returns for the second half of season seven on Saturday March 30. Executive producer Caro Skinner confirmed recently that the series will see the resurrection of classic monsters the Ice Warriors.