'Sons of Sam' is yet another long-winded, unsatisfying murder doc

Netflix's penchant for elongating stories for a documentary miniseries is well documented - no pun intended.

'Crime Scene: The Vanishing at the Cecil Hotel' spun the wheels for four episodes when, really, it could have been wrapped in two episodes. One episode probably would have gotten it there, if it went for a feature length. 'The Night Stalker', likewise, rattled along for four episodes before it eventually got where it was supposed to have been by the end of the second or third episode.

By contrast, 'Sons of Sam' is one that spins further out and that's just the point of it. The opening episode summarises the murders of David Berkowitz, initially known as the .44 Caliber Killer and later identified as the Son of Sam, in New York in the '70s. As you'd expect, the documentary harnesses the grime and grit of the city at that time, how it was truly a hellish landscape, utterly ripe for the kind of horror that Berkowitz would unleash on it. Out of this, we're introduced to Maury Terry - a fairly nondescript journalist who becomes fascinated with the murders, but begins to suspect that Berkowitz couldn't have acted alone. Indeed, he's certain that he couldn't have acted alone.

'Billions' star Paul Giamatti narrates the series as Maury Terry, explaining the rapidly spiralling conspiracy that links together David Berkowitz with a variety of lurid topics - a Satanic cult in Yonkers, a seedy multi-millionare who had an "orgy room" in his palatial mansion, snuff movies, Charles Manson, and even the Church of Scientology. The subtitle of the documentary is 'Descent Into Darkness' and really, that's what it is - Maury Terry diving into an abyss of madness and murder from which no clear answers emerge.

Director Joshua Zeman has some experience dealing with vast urban legends. His debut documentary, 2009's 'Cropsey', followed one such tale about a boogeyman-type character and, further on, a child kidnapper in Staten Island. In 'Sons of Sam', Maury Terry's investigation lasts decades. It begins with David Berkowitz, pulls through to the '80s where his book, 'The Ultimate Evil', becomes a topic on chintzy tabloid news shows like 'Inside Edition' and 'Geraldo' and folds into the Satanic Panic of the '80s and '90s.

In the midst of all this, however, interviews ping back to those in Terry's orbit and doubt begins to seep in - and not just in the fact that you've got people like Bill O'Reilly and Geraldo Rivera gleefully boosting Terry's theories. The New York detectives who captured Berkowitz consistently poo-poo Terry's outlandish conspiracies. One detective offers up a plausible explanation for the reasons for reopening the case involving Berkowitz by a Queen DA - namely, that the DA in question needed a boost in popularity. This is then counteracted immediately by the fact that the NYPD's investigation clearly ended when Berkowitz confessed and was wrapped up quickly to restore public order.

Like so many of Netflix's murder docs, there is a grim thrill to it all and it does hook you in. The aura of black magic, murder, Hollywood, and sex presents itself with a dark glamour in the story, but it's ultimately hollow. We're following Terry casting this wide net with progressively outlandish results, culminating with a face-to-face interview with Berkowitz himself that, frankly, bears almost no journalistic merit whatsoever. Interestingly, director Zeman includes these doubts in some of the talking heads afterwards. The frustrating part is that it's never followed up. We're never given any kind of straight answer as to whether or not Terry was right or not.

Like David Fincher's 'Zodiac', the ending can be construed as unsatisfying or perhaps exactly what we deserved for believing in all this in the first place. When you tie together these strands, when you pull shapes and meanings from signs and shadows, it's never quite what you think it is when you turn on the light.

In 'Sons of Sam', this is borne out by the flat ending and the lack of any real closure. It's not that there wasn't any to be made, but simply that the yarn ran out of wool.