9. Lost, 'The End' (2010)
There's polarizing, and then there's Lost. And the ABC show's series finale is no different: You either loved it or loathed it. After starting with an incredible opening act – a plane crash leaves dozens of survivors stranded on a mysterious tropical island filled with polar bears, smoke monsters and a hatch with set of seemingly magical numbers – the sci-fi series, which ran for six seasons from 2004-2010, turned into a muddled mess. Fans huddled around their televisions in hopes of getting answers to the myriad questions the show had racked up over the years. Instead, they were left with one giant head-scratcher to ponder: What the hell happened? Had it all been a moving spiritual allegory or one giant cop out? The debate rages on.