Whatever the craftsmanship, the skill with which the story is told, a documentary is only as riveting as its subject — be it some odd business or hobby, or a character it’s built around.

And that holds true for mockumentaries, scripted films meant to look like a non-fiction piece of reality, as well.

The first hour of “Skyman,” a portrait of an Apple Valley, California man haunted by an alien “visit” as a child, convinced that “visitor” is returning on his 40th birthday, is overwhelmed by the banality of the ordinary, working class and seemingly deluded life whose story it tells.

A generally flat performance doesn’t help when we’re seeing and hearing interviews meant to flesh in how Carl Merryweather (Michael Selle) lives, how his life has turned out and how much this event when he was ten shaped his life.

A psychologist tries to explain the mental traits of someone claiming to have met or been abducted or even “probed” by aliens, vouch, someone who “may be just a little bit lost.” A friend and a former employer vouch for Carl’s character even if they note he’s always been a little off.

And the sister he lives with (Nicolette Sweeney) alternately defends him and indulges him.

But the film hangs on actual interviews with Carl, and a third act finale that finally gives away the artistry and suspense-building skill of “Blair Witch Project” co-director Dan Myrick, who delivers an ending that can’t up for the first 70 minutes.

Because what comes through in that long, tedious buildup — sitting down with Carl and his sister, following Carl to a UFO convention in McMinnville, Oregon (an annual May highlight of the McMinnville calendar), trailing Carl as he buys gear he needs and preps for his birthday “reunion” — is a sense of a documentary filmmaker who doesn’t know the best questions to ask, what to leave in, what to edit out, and how much patience the average viewer has with watching “filler.”

See Carl unplug to fridge in his hotel room because he’s “sensitive to electromagnetic current.” OK, we get it. Do we need the set-up of following him down the hall, ducking into his room, and everything that comes before that payoff?

See Carl clumsily question a published “visitor” expert on his book about arcane details of the weather, exact location, etc. of that man’s experience. The guy can’t recall every specific, perhaps making a point Carl threw out there to excuse alien encounter narratives, that “there’s truth in the inconsistencies.”

He’s obsessed. We also get that. And the colorful cosplay going on all around him at the festival (Darth Vader, in a kilt, on a unicycle playing “Scotland the Brave” on his bagpipes) isn’t distracting him.

There’s dead time in and around every introductory scene, and everything that doesn’t drive the “They’re coming back for me” narrative makes “Skyman” — 10 year-old Carl’s description of who he saw  — feel like it’s ambling through quicksand.

His sister (more animated, conflicted and revealing) confesses that “For the longest time, I thought it was a cry for help.”

The occasional moment of drama from her, the camera-caught side-eyes of his equally-indulgent pal (Faleolo Alailima) don’t make up for making us sit through outtakes which a “real” documentarian would have left on the cutting room floor.

“This gas station has the best beef jerky!”

Selle finally makes Carl interesting enough to watch in that finale. But every scene he underplays before that sucks the life right out of “Skyman.” Embittered encounters with locals he’s known all his life, a pointless visit to the Integratron and other sites shown in the “real” UFO doc “Calling all Earthlings,” about UFO cultist George Wellington Van Tassel, desert treks to bury this or set up that are all played in the same flat note.

Knowing that to be the case, you’d think the editing strategy would have been different. Knowing the subject matter and genre (UFO docs are almost as common as Holocaust recollections), you’re not going to “surprise” the viewer with “I was visited when I was 10 years old.” Why burn so much screen time establishing how “ordinary” Carl is, other than this signature, all-consuming event of his past?

There are desert shots, night-vision treks and a few images that stand out. And as I mentioned, the finale eventually delivers something of a payoff.

But as alien encounter documentaries or mockumentaries go, “Skyman” is boringly earthbound.

MPAA Rating: unrated, profanity, smoking, alcohol

Cast: Michael Selle, Nicolette Sweeney, Faleolo Alailima

Credits: Written and directed by Daniel Myrick. A Gravitas Ventures release.

Running time: 1:33