The Waters of Mars has been written by showrunner Russell T Davies along with Phil Ford and was directed by Graeme Harper. This is only the second time Davies has co-written a story for Doctor Who, the recent Planet of the Dead being the first (with Gareth Roberts). Ford has previously written an episode of Torchwood and five stories in The Sarah Jane Adventures. Harper is also no stranger to the world of Who having directed episodes in both the 'classic' and new series.

Starring in Mars are: Lindsay Duncan (Rome); Peter O' Brien (Underbelly); Chook Sibtain (Doctors); Aleksander Mikic (Eastern Promises); Cosima Shaw (V For Vendetta); Gemma Chan (Project Catwalk) and Michael Goldsmith. O' Brien and Russell T Davies worked together ten years ago on Queer As Folk whilst Sibtain previously appeared in the Sarah Jane Adventures story, Warriors of the Kudlak. Duncan herself is no stranger to sci-fi as she provided the voice for fan favourite TC-14 in Star Wars Episode I: The Phantom Menace.

The broadcast date has not been confirmed though Russell T Davies has stated that the transmission date will be "Novemberish". This now means that the story could be broadcast on Halloween (as it falls on a Saturday this year) though it could also tie in with Children In Need or the show's 46th anniversary in the second half of November. Various other members of the production team, however, have referred to The Waters of Mars as the 'Autumn' special.

PLEASE NOTE: THE REST OF THIS ARTICLE CONTAINS SPOILERS!

As we revealed last month, Lindsay Duncan was spotted filming on the streets of Newport with David Tennant and a Wall*E-style robot. Also present at this scene was Ood Sigma - last seen in the Planet of the Ood telling The Doctor that his song would end soon. Sound familiar? Yup, Carmen did the very same thing at the end of Planet of the Dead. Coincidentally, Tennant was spotted filming a scene, for the same episode, wearing the spacesuit last seen in the first Ood two-parter from 2006.