How sad is this?

It's not great by any means, but it's a pretty good movie that didn't leave me filled with regret for investing time in it.

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.

Unshakable, witty and deeply felt, the film will be paying emotional dividends for a long, long time.