1. Benjamin Linus, 'Lost'
Like the magical mystery island that changed the lives of those aboard Oceanic Flight 815, Michael Emerson's performance as Ben Linus warped reality around him. Originally cast as a for a brief arc as a castaway who may or may not have been one of the sinister Others, the actor brought such a twitchy, soft-spoken intensity to the work that showrunners Damon Lindelof and Carlton Cuse reimagined the role as the series' Big Bad. Kidnapping, torture, mass murder, the sacrifice of his own daughter — there was nothing Ben wouldn't do to protect the Island from those he deemed unworthy of its secrets.
Yet his nerd-turned-bully demeanor contained a perverse charisma — particularly when played off his odd-couple relationship with Terry O'Quinn's John Locke, the Professor X to his Magneto — that slowly won audiences over. By the end of the series he was almost a co-protagonist, granted a shot at redemption he probably didn't deserve. A series is only as good as its bad guys; Lost had its problems, but Ben Linus was as good as bad gets.