While it’s true that Don Draper (née Dick Whitman) was a human disappearing act with a flair for reinvention and a surplus of the god-like confidence required to pull off a mid-air heist, it’s hard to imagine a less satisfying or plausible conclusion to one of the century’s most unpredictable shows. Of course, it’s possible that such unpredictability is the very thing that inspired certain fans to entertain such ridiculous theories; the further the final season moved away from convention, the more some people twisted the evidence into an understandable explanation — like a sleeping brain trying to organize a mess of neuronal soup into the narrative of a dream. People need to make sense of things. They need to find clear meaning in the muck of it all. While Don Draper was never going to be D.B. Cooper, both men proved that point in the same way. They had at least that much in common.

John Dower’s new documentary “The Mystery of D.B. Cooper” is a film that investigates what its namesake represents — namely, his anti-establishment allure, and the sense of possibility he stoked in the people who claim to have known him. As its title suggests, this movie is less about the man himself than it is about the mythos that developed around him. Or, at least, it should have been. But Dower, like so many of the obsessives he interviews here, grows too enthralled by the “who” of it all to stay on mission and meaningfully explore why it still resonates.   Of course, it’s easy to appreciate why Cooper’s stunt has taken root in the collective imagination — even at a time when hijackings were commonplace, this one stood out. It was like something out of a James Bond movie, and perpetrated by a man suave enough to earn that comparison. Dower has plenty of fun walking us through the heist in question. Fuzzy dramatizations of the skyjacking offer flimsy visual support for the talking head testimony Dower has recorded from the pilot and some of the stewardesses who were on board that fateful night, as these still-mystified survivors do their best to remember the well-dressed man who sat down in seat 18C of a Pacific Orient Airlines hop from Portland to Seattle and slipped a note into flight attendant Florence Schaffner’s purse just before takeoff (our first clue: Cooper knew enough about aviation to clock the exact moment when takeoff could no longer be aborted).

Schaffner assumed that Cooper was hitting on her, but he soon made a calm point of clarifying his intentions; it was only then that Schaffner noted the trigger resting in the passenger’s hand, her eyes following the button down to the dynamite-filled briefcase on his lap. One landing and another takeoff later, Cooper disappeared out of the aft door with a small fortune in cash and at least one of the four parachutes the Seattle police had sent aboard along with the money. And that’s when the legend began. Dower intercuts this account of the heist itself with grounded portraits of the potential suspects, his film keeping a keen eye on the people who claim to know who Cooper was. First on the list is a man named Duane Weber, whose impatient and serrated Pensacola widow Jo insists that her late husband said “I’m Dan Cooper” on his deathbed and decided that was reason enough to call the FBI after he died. Jo — who’s certain that Duane was confessing his truth — has a young “memory man” to help her keep the details straight, an absurdist touch that Dower casually explains away a bit further down the line. But if Duane Weber was D.B. Cooper, then what are we to make of Barbara Dayton, a gifted pilot who was designated male at birth and later became the first person in the state of Washington to receive sex reassignment surgery? Was the timing of her procedure (and the money required to pay for it) connected to the D.B. Cooper case, or have the doddering old couple who befriended her at the local airfield just seen “Dog Day Afternoon” too many times? By the time we get to the camera-ready Marla Cooper — who credibly boasts that she used to be a dead ringer for Twin Peaks resident Laura Palmer, and less credibly insists that her uncle was the infamous skyjacker — and the obsessive author who writes about D.B. Cooper from a shrine-like trailer out in the Oregon woods, all of these Cooper “truthers” are starting to sound less like reliable witnesses and more like people who say they were abducted by aliens. Dower, meanwhile, is happy to follow what little hard evidence we have, but is quick to brush past the overwhelming likelihood that Cooper didn’t even survive the jump, let alone live to brag about it. Why get bogged down in boring physics when you can get swept up into one of the rare mysteries this concrete world still has to offer? Somewhere, deep under the surface of Dower’s film, is an illuminating meditation on the relationship between the banality of modern living and the fantasies that people sell to the masses to help them cope with it. (Don Draper wasn’t D.B. Cooper, but he easily could have invented him.) “The Mystery of D.B. Cooper” is frustratingly short on context, but Dower still alludes to the suffocating despair of Seattle’s Boeing-centric economy circa 1971, and how — at the height of the Vietnam War — people were desperate for a taste of wonder in their lives. Someone even refers to Cooper as “a Robin Hood-type” folk hero, even though he didn’t steal from the rich and give to the poor so much as he stole from the banks and then threw the money out of a plane without sharing a penny of it.

Who cares? Americans love someone who beats the system, even if we ultimately have to foot the bill for it ourselves. There’s a direct line between D.B. Cooper and Donald Trump, but Dower is so entranced by the mystery at hand that he neglects to unpack what it might say about our collective need to believe in something more interesting than the truth. His film stalls out as soon as it embraces an investigative approach into Cooper’s life after the skyjacking, that dead-end detective work coming at the expense of a more abstract portrait of why people refuse to believe that Cooper died before his body even hit the ground. Or why some people were even flummoxed that the world’s most natural salesman found enlightenment in a Coke commercial instead of through becoming a notorious sky pirate, which is surely the more logical of those two options. “It’s about believing in something,” one of Dower’s subjects insists. But it’s also about not believing everything else. The more this documentary grows convinced that it’s actually about D.B. Cooper, the less it has to offer about the mystery he left behind.

Grade: C

“The Mystery of D.B. Cooper” premiered at DOC NYC 2020. It will premiere on HBO on Wednesday, November 25. Sign Up: Stay on top of the latest breaking film and TV news! Sign up for our Email Newsletters here.