I'll tell you why so serious

It really made me laugh, but for some moments I was tearing up because I could relate so much.

Let me be very fair here, this is not the best movie in my opinion. But, this movie is fun, it has purpose and is very enjoyable to watch.

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.