One thing that kept me viewing this documentary, since I'm too much skeptical to follow usual UFO documentaries till the end as they usually present preconceived assumptions, was the first dialogs between the operator and the police officer. They expressed inquiry and skepticism with a satirical approach to usual misinterpretations. As the episode develops the tunes of the dialogs vary from genuine expositions labeled by sober perplexity and the changing of an operator's satirical tone to a trembling wondering.
It was explicit for me at that time that every person involved was being serious, analytic and not being part of a sensationalist tabloid news.
The number of reliable police officer witnesses increases as it allows to mark a distant trajectory of the unknown peculiar sight, corroborating that the sight itself, independently of what it was, was real. The vast distance of the route put away the hypothesis of a misinterpretation.
In opposite to usual sensationalistic UFO cases, when it's assumed a priori that each case represents the irrefutable proof of alien intelligence, this one shows a development of perplexity, attempt of describing something unexplained in the common database of known either artificial or Geo-natural phenomena, coining not a dogma but a demand for explanation, either with scrutinized testimonies, contact with military forces and specialized people for an accurate recreation of what they saw.
The tendency for accumulating data searching various fields, logically scrutinizing valid hypothesis, therefore an open exposed approach and scientific by inherence in opposition to a secretive threatened and single like relic proof, convinced me this is one of the best documented, corroborated cases in UFO history, of course presented in a same way rationalist, logic and very well constructed documentary.