Its a film about rotten people, Greed and Lust, it follows to two outsiders of the British aristocracy, through sex appeal they attract the eye of wealthy aristocrats, not intentionally I must say, however money is certainly a powerful aphrodisiac.
One fatal flaw is that they fall for each other instead of their respective supposed partners. The tiring choice between greed and lust is ever so present, even if greed is presented as tiring and tedious.
The character types are generic, but in my opinion, it is purposeful, because the film's main goal is about the moral vacancy and plot.
It is not too say, there were no good performances. My queen, Scarlett Johansson and Jonathan Rhys-Meyers provided an exquisite performance regardless.
Overall, Greed and Lust is the key to this movie, do not read too much into the characters, rather read into their actions and choices.