Science fiction and fantasy have ruled television for over 50 years, but some shows have brightened our screens and supercharged our brains more than others. Here's our list of the 100 greatest science fiction/fantasy shows of all time. How did we determine these rankings? Using science. That means that if you disagree with the shows we included, or the order we ranked them in, you are anti-science, and must go back to living in caves and eating animals you killed yourself, with your bare hands.