The leads have great chemistry, there's some really interesting imagery, and several of the actors do well with dual roles. The idea of a body-jumping serial killer is also a solid idea for a series. And that subplot that turns the poor-girl-meets-rich-guy story into something more sinister is flat-out brilliant.

Unfortunately the writers take this whole promising mix and sacrifice it on the altar of edginess.

I'm not saying this as someone with no tolerance for darkness in movies or tv; I often enjoy dark themes, gory effects, and tragic twists. I actually spend more time watching horror movies than I do dramas, so something with Possessed's genre mix should be right up my alley.

The problem here isn't the mash-up of love story and tragic thriller. It's that the series establishes one tone for its first three quarters and then devolves into a pointless, mean-spirited mess. Once you realize how far the show's willing to go, there's very little suspense. Knowing that nearly every situation will end in the worst possible way turns the final quarter of the series into a slog fest. There's plenty to be said for raising the stakes, but that's not what this show does. Instead it takes its stakes and just chucks 'em, flinging those poor stakes hard enough to distance the viewer from nearly everything in the show worth caring about. With that kind of random momentum, it's no wonder the last episode lands with a thud.

"Saving the world" is not a concrete enough goal to carry me through that final showdown. Good stories are about more specific things like characters and relationships. Watching Detective Kang struggle through to save a few comrades or his love interest would have been riveting even if things didn't turn out how I wanted. But having him just trudge on (because that's what a hero does!) turned a great show into my biggest drama series disappointment yet.