Bedlam

Strong first series followed by a weak last one. Advice ... recasts never work!

Moody horror filled with pretty, oversexed people. It never quite comes together from a plot/metaphysics viewpoint, but it does create a satisfyingly morbid story arc at the end.

The cast changes almost completely in the second season, and at the beginning of that season it feels like suspicious recasting, but if you keep watching it does hang together.