the G-man wrote:
Heroes: Sylar was supposed to die after the first season. Instead he practically became the star of the show (and, to some, its downfall).
I always thought the downfall of Heroes was its inability for any character to be doing the same thing for more than two episodes in a row after the first season.
Was Hurley in Lost originally intended to have such a large role? He looks just a little bit like a Mary Sue, but then again he was the last original main character to have a flashback and his first non-comic relief role was when he was gathering the census in episode 9 or so.
Your comment about Sylar reminded me of one more: Jesse in Breaking Bad.
Jesse would have died in the first season if there hadn't been a writer's strike.