All told, quite delicious. Reminded me a lot of Gosford Park - glittery, sharp, surface-obsessed society types (for whom I feel a considerable amount of sympathy, which is as much a reflection of my own predispositions as it is a sign of the film-makers' craft) gather in self-contained early twentieth century period setting, converse wittily and cuttingly, score points and strike sparks off one another, and eventually find one of their number dead - and I liked it almost as much.
Excellent turns from all concerned, aided by some really good script-writing and characterisation, and plenty of shades and nuances without sight of the big picture being lost...it feels like a whole other world, all wealth and power and artifice and excess, but there's a fragility to proceedings which is tied into the human side of the movie; "W.R." and Marion in particular emerge as multi-faceted, complex figures impelled by circumstance and all kinds of necessities, and in the end it's the cynical Elinor, perhaps the most self-conscious as well as, despite her sardonic exterior, the most humane of the ensemble, who encapsulates what it's really all about as she recounts her melancholy recurring dream, bringing out the sadness - the hollowness - just beneath the surface of the bright stage.