Which TV show has the best opening credits sequence of all time?S

A great opening sequence tells you more than just a TV show's backstory: it drags you, kicking and screaming, into the show's world. A truly great opening sequence is a masterpiece of raw style. But which science fiction or fantasy TV show has the absolute best opening credits?

Please include a clip or still image of the credits you love the most. And if it's not immediately obvious, please share the name of the show in question. Thanks!

Top image: The Prisoner.