"Cold War" is the eighth episode of the seventh series of the British science fiction television series Doctor Who. It first aired on BBC One on 13 April 2013, and was written by Mark Gatiss and directed by Douglas Mackinnon.
In the episode, alien time traveller the Doctor (Matt Smith) and his companion Clara Oswald (Jenna-Louise Coleman) land on a Soviet submarine in 1983 during the Cold War, where the Ice Warrior Grand Marshal Skaldak breaks loose and plots revenge against humanity.
"Cold War" reintroduces the Ice Warriors, who were last seen in the Third Doctor serial The Monster of Peladon (1974). Bringing back the monsters was Gatiss' idea, and he convinced executive producer Steven Moffat by coming up with new things to do with them. The Ice Warriors' costume was improved but not significantly redesigned, as the production team felt they were not well known enough. The episode was filmed in June 2012 on a submarine set, as the story is a closed "base-under-siege". "Cold War" was watched by 7.37 million viewers and received generally positive reviews from critics.
Plot
A Soviet submarine is sailing near the North Pole in 1983 during the Cold War. In the submarine's cargo hold a sailor prematurely begins to defrost a block of ice that Professor Grisenko believes contains a frozen mammoth, and is attacked by an Ice Warrior.
The submarine begins sinking as the Ice Warrior runs amok. The TARDIS materialises inside the submarine and the Eleventh Doctor and Clara tumble out. The Doctor convinces Captain Zhukov to maneuver the submarine to the side, landing it safely on a ridge and preventing it from imploding. During this the TARDIS dematerialises by itself. The Doctor encourages the crew to be peaceful to the escaped Ice Warrior, Grand Marshal Skaldak, but the ship's executive officer Stepashin knocks out Skaldak. Knowing that Skaldak will desire vengeance for being attacked, the Doctor and the crew chain Skaldak.
Clara volunteers to speak to Skaldak to try and calm him, relaying the Doctor's words to Skaldak, though he knows that the Doctor is listening. The Doctor informs Skaldak he was encased in the ice for 5000 years. Skaldak laments the loss of his daughter and his people; however, the Doctor tries to comfort him with the knowledge that the Ice Warriors still live, just not on Earth or Mars. Skaldak does not believe the Doctor and stops broadcasting his distress call to the other Ice Warriors. The Doctor surmises that, thinking himself to be the last of his kind, Skaldak has nothing left to lose. He grabs and kills three members of the crew, including Stepashin.
Having learnt of the ongoing Cold War and the doctrine of mutually assured destruction from Stepashin, Skaldak plans to use the submarine's nuclear missiles to provoke a global thermonuclear war and destroy humanity as revenge for the humans attacking him – under the Martian code humanity as a whole has declared war on the Ice Warrior race by assaulting him. Reaching the bridge, he is able to connect himself to the submarine's missile guidance systems and activate the missiles. The Doctor and Clara are attempting to persuade Skaldak to show mercy when the submarine is rocked by a tractor beam from above: the Ice Warriors heard Skaldak's distress call and haul the submarine to the surface. Skaldak is beamed aboard the Ice Warriors' spaceship and deactivates the missiles remotely. The Doctor discovers the TARDIS has relocated to the South Pole.
Production
The Ice Warriors were a well-known villain of the original Doctor Who series. They appeared alongside the Second Doctor (Patrick Troughton) in The Ice Warriors (1967) and The Seeds of Death (1969) and returned in the Third Doctor (Jon Pertwee) stories The Curse of Peladon (1972) and The Monster of Peladon (1974). Showrunner Steven Moffat had originally been hesitant to bring back the Ice Warriors, worrying that they were seen as "the default condition for what people thought of as rubbish Doctor Who monsters — things that moved very, very slowly and spoke in a way that meant you couldn't hear a word they said." Writer Mark Gatiss, however, was a fan of the Ice Warriors' stories and had been campaigning to bring them back. In a phone conversation with Moffat that was originally supposed to be about their show Sherlock, Gatiss pitched new and "very clever ideas" of what to do with the Ice Warriors, and Moffat agreed. What sold Moffat were the submarine setting and seeing what the Ice Warriors looked like underneath their suits. Gatiss felt that the Ice Warriors had a lot of gaps in their timeline and had not been featured in a while, which allowed a lot of room to explore them.