Lost (2004)

The season three finale pulls a piece of sleight of hand so neat that the usual reaction is a puzzled frown, then a shout. Sit where you can see both. Lost hooks fast, with a pilot that ends on a genuine jolt, and its island mysteries are made for two people theorizing on the same couch between episodes. The later answers do not satisfy everyone, so sell it on the characters and the ride rather than the solution. Knowing where it goes makes the flashback structure a joy to rewatch, because you notice who was already connected to whom.