13 Intense Movie Performances That Are Incredibly Difficult To Watch

11. Natalie Portman - Black Swan

In the grand history of body-shock film-making, the moment in The Black Swan when Natalie Portman peels her cuticle back is quite possibly one of the most despicably affecting of all, but it is the perfect culmination of Nina Sayers' descent to madness.

Her portrayal of the unstable, unravelling ballerina is hugely difficult to watch, thanks to the rawness of Portman's performance, and there is something deeply unnerving in the way director Darren Aronofsky messes with the audience's expectations of reality, tearing down boundaries and making even the most jarring of scenes appear authentic.

Portman's performance descends to such a degree that she is no more than an angry open wound, and even as it becomes clear that she might well be evil (at least in her own psyche) it's hard to watch how far she falls.