When almost all "UFO" documentaries I've seen (and, as a person with a formal science background, I'm a tad less than proud to admit that I've seen'em all) are extremely one-sided --often ridiculously so, this one is about as good as they get at attempting to realistically examine much of this vast phenomenon.
Not only is a great deal of never-before-seen material presented, but this is one of a very few that would be satisfying to both "true believers" and scientific/analytic/skeptic-types alike.
If the subject matter has ever interested you, regardless of your mindset, I highly recommend this documentary, a MUST-view if only for its well balanced approach to a field which has historically shown to be most difficult to empirically and/or unemotionally examine, e.g., the ridiculous --at least from a true science perspective-- yet common (even among some "scientists," e.g., Carl Sagan, et al.??) MIS-belief that "extraordinary claims require extraordinary evidence" (i.e., *ALL* "empirical" research requires the *SAME* amount of statistical analysis, evidence, proof, etc...).
My rating: 9 out of 10 (10 out of 10 for serious researchers, both journalistic and academic, as well as, would-be researchers)