HAVE YOU ever noticed just how many feature-length documentaries have been made and released in the past decade? It’s quite stunning, really.

This explosion in documentary filmmaking can mostly be chalked up to two factors: the digital revolution (which suddenly allowed “broadcast-quality” sound and visuals to be captured for a miniscule fraction of the cost of traditional 16mm or 35mm celluloid film), and –once again—the digital revolution (which allowed for low-budget and big-budget docs alike to receive international distribution online, something which most never received in the past, no matter how incredible they were).

However, there was a time, right up until the late 1990s, when taking an independent documentary film from inception to theatrical release took a tremendous amount of money, effort and luck in order to reach fruition. Back in those days, it was nearly impossible for someone to come up with the finances, equipment and crew required to shoot and post-produce even the most bare-bones, full-length docs – especially if their subject matter was even remotely out of the interests of mainstream viewers.

As a result, scores of worthwhile docs which actually did get completed never wound up with any meaningful distribution, and many remain essentially “lost” and unseen to this day.

Unearthing some of those forgotten treasures of non-fiction filmmaking was the idea behind the Psychotronic Film Society’s occasional showcase “The Greatest Documentaries You Never Saw,” which occurs every couple of months as part of the PFS’ ongoing Wednesday night series of marginalized or underappreciated world cinema at the Sentient Bean Coffeehouse.

Because the goal is to have audience members arrive without any preconceived notions of what sort of documentary they will see, the exact titles and specific details of each carefully curated selection remain a secret until showtime. However, they all share these common denominators: these titles are respected and acclaimed by other documentary filmmakers (and may have won industry awards); they focus on unusual or unconventional subject matter; they are extremely difficult to find and view otherwise.

This can be said of the “Mystery Doc” being screened at the Bean on Jan. 29 was the very first directorial effort by a documentarian who would go on to become one of the most revered and influential independent auteurs of his generation, and this extremely strange look at the inhabitants of a small community just a few hours from Savannah is a gem which has never been released on DVD, Blu-Ray or digital streaming anywhere in the world. Showtime is at 8 p.m.