<P> With the show's 2005 revival, executive producer Russell T Davies stated his intention to reintroduce classic icons of Doctor Who . The Autons with the Nestene Consciousness and Daleks returned in series 1, Cybermen in series 2, the Macra and the Master in series 3, the Sontarans and Davros in series 4, and the Time Lords including Rassilon in the 2009--10 Specials . Davies' successor, Steven Moffat, has continued the trend by reviving the Silurians in series 5, Cybermats in series 6, the Great Intelligence and the Ice Warriors in Series 7, and Zygons in the 50th Anniversary Special . Since its 2005 return, the series has also introduced new recurring aliens: Slitheen (Raxacoricofallapatorian), Ood, Judoon, Weeping Angels and the Silence . </P> <P> Besides infrequent appearances by the Ice Warriors, Ogrons, the Rani, and Black Guardian, three adversaries have become particularly iconic: the Daleks, the Cybermen, and the Master . </P> <P> The Dalek race, which first appeared in the show's second serial in 1963, are Doctor Who's oldest villains . The Daleks are Kaleds from the planet Skaro, mutated by the scientist Davros and housed in mechanical armour shells for mobility . The actual creatures resemble octopi with large, pronounced brains . Their armour shells have a single eye - stalk, a sink - plunger - like device that serves the purpose of a hand, and a directed - energy weapon . Their main weakness is their eyestalk; attacks upon them using various weapons can blind a Dalek, making it go mad . Their chief role in the series plot, as they frequently remark in their instantly recognisable metallic voices, is to "exterminate" all non-Dalek beings . They even attack the Time Lords in the Time War, as shown during the 50th Anniversary of the show . They continue to be a recurring' monster' within the Doctor Who franchise, their most recent appearances being in the 2015 episodes "The Witch's Familiar" and "Hell Bent". Davros has also been a recurring figure since his debut in Genesis of the Daleks, although played by several different actors . </P> <P> The Daleks were created by writer Terry Nation (who intended them to be an allegory of the Nazis) and BBC designer Raymond Cusick . The Daleks' début in the programme's second serial, The Daleks (1963--64), made both the Daleks and Doctor Who very popular . A Dalek appeared on a postage stamp celebrating British popular culture in 1999, photographed by Lord Snowdon . In the new series, Daleks come in a range of colours; the colour denoting its role within the species . </P>

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