It would be unwise to underestimate our collective need to witness the abject humiliation of our fellow human beings. This truth is underscored by the ongoing popularity of reality TV, and is semi-officially recognized in the annual Darwin Awards, given to those who "improve the gene pool by removing themselves from it" - dimwits who kill themselves with ill-advised scientific experiments and other stupid human tricks.

Definitely not us. We're still alive.

This form of schadenfreude may, in part, explain the attraction many movie buffs feel for unquestionably bad movies. To see others fail horribly at a task we think we could probably do pretty well is to succeed a little while risking nothing. And nobody gets killed.

Which brings us to "Troll 2," a movie that, on the evidence presented in the entertaining documentary "Best Worst Movie," is so bad that I and even you - well, I'm not so sure about you - could actually do better.

"Troll 2," originally released in 1990, was not, despite the number in the title, the sequel to anything. Nor did it feature any trolls. It was a horror movie about goblins, a terrible idea to begin with.

The movie sank upon theatrical release, but in the past few years, with the spectacular growth of social media as a brand new way to waste time, it has earned a certain degree of cult worship. The Internet Movie Database ranks "Troll 2" as number 64 in its list of the 100 worst movies ever made, but its true fans think that's way overestimating its quality. One devotee says "Troll 2" stands out among really bad movies because the filmmakers appear to have started out with some idea of how to make a movie, but then suffered severe brain damage.

Some of the original stars, long lost into the world of ordinary people, now make appearances at horror film conventions and trash-movie festivals. Leading the way is the garrulous Alabama dentist Dr. George Hardy, who had the lead role and is not too proud to stand in front of a stack of DVDs and play the huckster for horror-fest patrons. "Worst movie ever made," he proclaims, with a proud smile.

"Best Worst Movie" shows you as much of "Troll 2" as you can stand - it's basically about a family trapped at a cabin in the woods by goblins, to the extent it is about anything at all. But the documentary focuses on what has happened to the cast and crew since "Troll 2."

The director, Michael Paul Stephenson, played a kid in the movie. He tracks down the original cast and the filmmakers and interviews them. This time, he's in charge, and he has a lot of fun with his counterpart on "Troll 2," obscure Italian schlock director Claudio Fragasso, who seems to think he made something approaching art in Utah about 30 years ago.

Fragasso is so arrogant, whatever he gets, he has coming to him. Otherwise, on the whole, the movie has a sweet spirit, in part because Dr. Hardy seems like such a genuinely nice guy. However, Stephenson makes one serious misstep.

Most of the survivors of "Troll 2" seem to be in on the joke, but the woman who played the mother of the goblin-besieged family clearly has mental problems, beginning with agoraphobia. The first visit with her is painful enough, but probably necessary to tell the full story. But dragging a camera back to her house - her fortress - for a lengthy second interview was needlessly cruel.