The Daleks are a fictional extraterrestrial race of mutants from the British science fiction television series Doctor Who. Within the series, Daleks are cyborgs from the planet Skaro, created by the scientist Davros during the final years of a thousand-year war against the Thals. They are genetically engineered Kaled mutants integrated within a tank-like or robot-like mechanical shell. The resulting creatures are a powerful race bent on universal conquest and domination, utterly without pity, compassion or remorse. Various storylines portray them as having had every emotion removed except hate, leaving them with a desire to purge the Universe of all non-Dalek life. Collectively they are the greatest enemies of the series' protagonist, the Time Lord known as the Doctor. Their catchphrase is "Exterminate!"