american horror story -- season finale

i've not been keeping up with this show. so when a friend invited me to watch a couple of prior recorded shows then watch the season finale tonight i said yes. now i'm up to speed and yes it's still a very creepy show. i wonder how long the dark tone and intensity can be sustained. i read a very good analysis about the show reflecting contemporary economic ills. that a middle-class family who are bogged down by their financial burden of their house and that they cannot leave it if they could are suffering and the cause is the house itself. sounds about right. still, i was surprised with the twist at the end. jessica lange's character is getting juicier and juicier. yet, there seems to be a peace set upon the family that tempered the darkness just a bit . was it because show creator and producer ryan murphy wished to make a christmas theme? appears so as the family, after much travail, stand before a fully decorated and lighted christmas tree while two of the other occupants, signficant players, of the house -- they are ghosts -- watch from another room thru barred glass. the peace won't last of course. madness lives in that house. fascinating ending to a very good show. can't wait for next year.