23. DOCTOR WHO (1963-Present)
Developed by Sydney Newman

The BBC's timeless Doctor Who is a 44-year argument for proper sci-fi priorities: (1) an ecstatically tangled, infinitely renewable story line and (2) an understanding that all science fiction, however time- and space-spanning, is local. (Top-flight special effects? Not, as it turns out, crucial.) The Doctor, a Time Lord, powerful but dispossessed, hops worlds and epochs like subway stops, but in spirit he never really leaves London.

POP CULTURE LEGACY With its playful yet sincere commitment to social allegory, Doctor Who has always been a post-empire fantasy — unerringly progressive, but wary, dark, and full of doubts about human goodness.

THE BEST BIT Check out the first season of the newest incarnation, featuring Heroes' Christopher Eccleston as the ninth Doctor (the best ever — apologies to Tom Baker) and the piercing, poignant wit of writer Russell T. Davies. —Scott Brown