Spike (James Marsters) - Buffy (1997-2003), Angel (2003-2004)
Alright, so this was a tricky one - having limited ourselves to one vamp per show, did we choose dark, broody Angel (David Boreanaz) or Brit bad-boy Spike? Ultimately it was James Marsters's peroxide blood-sucker who won through because, let's face it, Spike is just more fun than Angel. Originally introduced as a central villain in Buffy's second season, Spike's quick wit and cheeky charm quickly won him a legion of admirers.
Marsters was eventually made a series regular, with Spike turning to the side of good (well, sort of) and when Buffy drew to a close, Joss Whedon still saw potential in the character and transferred him to spinoff series Angel for its final season. Alright, so his British accent might have been a little shaky on occasion, but Spike is still a top TV vampire!