Doctor Who is the longest running science fiction television programme in the world, first going to air on British television in 1963. New episodes continue to be made and aired today, and they attract a whole new generation of fans. In Britain and elsewhere, the show has become a cult television favourite and has influenced generations of British television professionals, many of whom grew up watching the series.

The series depicts the adventures of a mysterious time-traveller known as "the Doctor" who explores time and space in his TARDIS time ship with his companions, solving problems and righting wrongs. Unlike other programmes, when the actor playing "the Doctor" retires, the character is not retired also, but is simply given a new incarnation, complete with a new personality.

The Daleks are an extra-terrestrial race of mutants that were introduced in December 1963 in the second Doctor Who serial. They became an immediate hit with viewers, featuring in many subsequent serials and two 1960s motion pictures. They have become synonymous with Doctor Who, and their behaviour and catchphrases are part of British popular culture. "Hiding behind the sofa whenever the Daleks appear" has even been cited as an essential element of British cultural identity, along with Bovril and afternoon tea. The Daleks were created by writer Terry Nation and BBC designer Raymond P Cusick.

The Daleks are a grotesque mutated organism integrated with a tank-like mechanical casing made of "dalekanium". The resulting creatures are a powerful race bent on universal conquest and domination, utterly without pity, compassion or remorse (as all of their emotions were removed except hate). They are also, collectively, the greatest alien adversaries of the Time Lord known as the Doctor. Their most famous catchphrase is "EX-TER-MI-NATE!", with each syllable individually screeched in a frantic electronic voice .

The word "Dalek" has entered the Oxford English Dictionary and other major dictionaries; the Collins Dictionary defines it rather broadly as "any of a set of fictional robot-like creations that are aggressive, mobile, and produce rasping staccato speech". It is also a trademark, having first been registered by the BBC in 1964 to protect its lucrative range of Dalek merchandise.

Raymond P Cusick with one of the replica Genesis of the Daleks props. Cusick was responsible for the original design of the Daleks in the 1960s