The official blurb is:
The story follows medical student, Mary Mason, as she becomes increasingly broke and disenchanted with the surgical world she once admired. The allure of easy money sends Mary into the world of underground surgeries which ends up leaving more marks on her than her so called 'freakish' clientele
I wasn't really sure when I sat down to watch it what kind of movie it was going to be at all. Supposedly it is a "horror/thriller" movie, but usually horror movies are filled with gratuitous blood and guts, the plot mainly existing to navigate you from guts to boobs to guts again. That's not what American Mary is (although there's a decent amount of blood). What it is, is a sort of surreal look at the odd twists that life can take. I'm not sure if it was supposed to be disturbing or not, but I actually found it uplifting in an odd way.
If you liked Fargo or Sweeny Todd, there's a pretty decent chance you'll like American Mary. They're not really the same kinds of movies, but they have the same aesthetic sensibility.
9/10 from me.