The 'Doctor Who' 50th anniversary episode just got a whole lot scarier...
One writer on the hit BBC sci-fi show, Robert Banks Stewart, has hinted that fans will see not only the return of the Zygons (previously reported) but also appearances from the Timelord's most menacing enemies - the Daleks and the Cybermen.
"The Zygons are in there with all the others - particularly the Daleks and the Cybermen," Banks Stewart told Digital Spy.
The writer, who created shape-shifting aliens the Zygon which first appeared in 1975's 'Terror of the Zygons' opposite Tom Baker's Fourth Doctor, also penned 'The Seeds of Doom' (1976).
Details of the plot for the anniversary episode are being kept under wraps. But the BBC have confirmed David Tennant and Billie Piper are to return for the one-off special episode.
It will be the first time Tennant has returned to his role as the tenth Doctor, which lasted from 2005 to 2010.
Piper, who played companion Rose Tyler for two series, last appeared in Tennant's final episode 'The End of Time'.
Jemma Redgrave and 'Tinker Tailor Soldier Spy' actor John Hurt have also been confirmed to co-star in the 3D anniversary show in November.
British actress Carole Ann Ford (centre, right) makes a horn sign at a Dalek from the BBC television science fiction series 'Doctor Who', at the Daily Mail Schoolboys' and Girls' Exhibition at Olympia, London, 28th December 1964. In the series, Ford plays Susan Foreman, the companion of the first Doctor, played by William Hartnell. (Photo credit: Victor Drees/Evening Standard/Hulton Archive/Getty Images)
Dr Who encounters the ancient Aztecs in an episode of the famous TV series in 1964. From left to right, the actors are John Ringham, William Russell, Jacqueline Hill, William Hartnell (1908 - 1975) and Keith Pyott. (Photo credit: Moore/Fox Photos/Getty Images)
British actors Tom Baker and Elisabeth Sladen pose in 1974, who star in the new BBCTV series 'Dr Who'. (Photo by Victor Blackman/Express/Getty Images)
Tom Baker as the new Dr Who in 1974. He is shown here with a Cyberman and his assistant Sarah Jane Smith, played by Elisabeth Sladen, at the BBC television centre. (Photo credit: Frank Barratt/Keystone/Getty Images)
Dr Who (actor Peter Davison) and female companions of the Doctor's past and present pose in 1983. (l-r) Louise Jameson, Carole Ann Ford, Caroline John, Sarah Sutton, Elisabeth Sladen and Janet Fielding. (Photo credit: PA)
Paul McGann (as The Doctor) and Daphne Ashbrook (as Dr. Grace Holloway) in Doctor Who, shown in 1996. (Photo credit: WENN.com)
Actress Catherine Tate arrives at the press launch of 'Dr Who' series 4 at the Apollo West End in 2008 in London. (Photo credit: Dave Hogan/Getty Images)
Doctor Who, played by Sylvester Mccoy, poses with his companion Melanie, played by Bonnie Langford, in 1987. (Photo credit: Photoshot/Getty Images)
Doctor Who, played by Colin Baker, with companion Peri, played By Nicola Bryant in 1986. (Photo credit: Photoshot/Getty Images)
20th November 1980: Tom Baker, who plays Dr Who in the childrens TV series, is to marry Lalla Ward, who plays his assistant Romana in the series. (Photo by Keystone/Getty Images)
1980: Actress Lalla Ward, Dr Who's assistant in the BBC television series, riding K9, the doctor's robotic 'dog', in a park (Photo by Hulton Archive/Getty Images)
Actor Jon Pertwee, a former Dr Who, and actress Elisabeth Sladen, who played his companion in the series, at Heathrow Airport where they departed to Miami to attend a Dr Who convention (PA)
Tom Baker, as Doctor Who, and Mary Tamm as his companion, Romana, on the set of the BBC television science fiction series 'Doctor Who', at BBC TV Centre, London, 25th April 1978. (Photo by Fred Mott/Evening Standard/Hulton Archive/Getty Images)
English actors Jon Pertwee (1919 - 1996) and Elisabeth Sladen (1946 - 2011) outside BBC TV Centre, London, 26th June 1973. Pertwee and Sladen play Doctor Who and his companion Sarah Jane Smith in the British television series 'Doctor Who'. (Photo by William H. Alden/Evening Standard/Hulton Archive/Getty Images)
DR Who: Billie Piper, Christopher Eccleston
Bernard Cribbins (and David Tennant collect the award for best Drama received for Dr Who during the National Television Awards 2010.
The eleventh Doctor Who, actor Matt Smith, and his companion Amy Pond, actress Karen Gillian, arrive at the screening of an episode of the new Doctor Who series at Cineworld, Cardiff (Ben Birchall/PA Wire)
James Corden and Matt Smith take a break from filming the BBC sci-fi series Doctor Who Penarth, Wales. Photo: WENN.com
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