Review: too many `` serious issues '' 
Sentiment: negative

Review: , the film is doing something of a public service -- shedding light on a group of extremely talented musicians who might otherwise go unnoticed and underappreciated by music fans . 
Sentiment: positive

Review: serious suspense 
Sentiment: positive

Review: non-exploitive approach 
Sentiment: positive


Review: never bothers to question why somebody might devote time to see it