I am baffled that this film happened in the first place, which is a credit to the people that made it. After all you take a whole pile of really crappy people and have them do an awful thing to an unsuspecting person.... and then you make a film about it?
For the first 45 minutes I was a little unsure about the film but then it started to come together for me. The following helped:
Nobody is painted in a good light here
It is a dark comedy
At some point you feel bad for most of the characters (which is a testament to how awful the other characters are)
At no point does it take itself too seriously
It does not pretend to tell you what actually happened
At times it breaks down the fourth wall
The following did not help:
They dressed up Margo Robbie to look like Harding. Very, very distracting.
I don't know that this story needed to be told (and truthfully, I don't really know that it actually was told). All in all they did an amazing job telling the story of a very said lot.