A list of the best sci-fi shows and best sci-fi series of all time, as ranked by hundreds of Ranker voters. This list includes long-running sci-fi TV shows like Doctor Who as well as some of the best cancelled shows of the genre. Science fiction TV shows have been around for decades, and some of the longest running shows have fallen into this category. Popular shows such as Star Trek have enjoyed several incarnations, and fan-favorite shows like "Firefly" and "The X-Files" have made the crossover from TV to the big screen.
Vote for your favorite science fiction shows to move them to the top of the list, or press re-rank to create your own list of your favorite science fiction series. Be sure to stop by to vote on the best British sitcoms and best current TV shows airing right now.
http://www.ranker.com/crowdranked-list/the-best-scifi-television-series-of-all-time,
Firefly
Battlestar Galactica
Buffy the Vampire Slayer
Doctor Who
Stargate SG-1
Star Trek: The Next Generation
Star Trek: The Original Series
The Twilight Zone
The X-Files
Fringe