3. LOST (ABC, 2004-2010)

Mystery: What is the island?

Since the first frame of the first episode, the mystery behind the Lost island was the driving force behind the entire show. Nobody knew quite what it was or why the plane crash victims were stuck there, but everyone seemed to have their own theory on the matter. Books were written on it, websites were dedicated to it, and countless stoned college students debated their ideas for hours on end.

Through six seasons of varying quality, the show introduced numerous mysteries to its rabid fanbase, but everyone’s focus always came back to the island itself. Eventually, alternate realities and timelines muddled the main narrative somewhat, and it left some longtime fans of the show disappointed with the series finale; however, when a mystery is as long-lasting and anticipated as this one, the final reveal is always bound to fall short of some people’s expectations.

If you ask us, the more pressing mystery is how a dude like Hurley (Jorge Garcia) could stay so chunky while stranded on an island for years on end.