Find an actor or actress who has been in THREE successful television shows. Prime time, running for at least two seasons, television shows. Game shows do not count. No reality, they've got to be a character. No daytime soap operas, they're an incestuous lot. Playing a minor character does not count. For at least one series, they have to be one of the major roles. Cartoons do count, but only if it follows the above criteria (Family Guy, Simpsons, whatever).
So Seth Green, for example doesn't count. Greg the Bunny didn't last, he was on Buffy for two seasons, Family Guy counts, but he wasn't on Angel long enough. William Shatner does count: Star Trek, Boston Legal, TJ Hooker.
Any questions will be unscreened and clarified, so ask them in comments independent from your guesses.
IMDB use is permitted (as if I could stop it). Comments will be screened, highest score gets a prize.
EDIT: PLEASE INCLUDE THE NAMES OF THE SERIES, SO I CAN VERIFY YOUR CLAIMS MORE EASILY