It's funny, it's tense, it features two great performances from two actors and the director expertly creates a web of odd tension where you actually don't know what is happening for the majority of the run time.

A great movie, one of the best of this year. There was a bit of confusion at one point in the plot, but nothing serious.

Exactly the movie you think it is, but not the movie you want it to be.

One of the most extraordinary films you will see this year. Take that as you want.