There’s a scene towards the end of the upcoming Kings of Leon documentary (airing 10 p.m. Sunday on Showtime) that almost foreshadows the recent cancellation of their U.S. tour after lead singer Caleb walked off the stage in Dallas saying, “I gonna vomit, drink a beer. Then I’m gonna come back out, and I’m gonna play three more songs.” He never came back.

The scene in “Talihina Sky: The Story of Kings of Leon” is footage from the 2009 tour that drummer Nathan shot where Caleb pushed the other band members — who’re also brothers and a cousin — too far.

Nathan snaps, “Sit down and shut your f---ing mouth! We have made you, you little piece of s---!” It’s a perfect example of what many believe is the underlying tension within the Grammy-winning band. Caleb’s ego and excessive drinking has caused a rift among a foursome that was once as close as humanly possible.

Caleb, Nathan and Jared grew up the sons of a Pentecostal preacher spending much of their youth traveling the South for church revivals their father was putting on. It’s easy to imagine the bond that developed among three boys who were home-schooled and never spent enough time in one place to make friends.

“Talihina Sky” relishes in showing these roots (in Tennessee and Oklahoma) and how the band still revisits them regularly with family reunions in rural Talihina, OK at the shanty compound of the band’s grandparents, Betty-Ann and Leon Followill — who they’re named after.

It’s a strange, at times disheartening, place reminiscent of the Eastern Kentucky Appalachia in “Harlan County U.S.A.” and some of the characters residing there could easily fit in with “The Wild and Wonderful Whites of West Virginia.”

The Talihina compound is important because it was the boys’ first exposure to a less “moral” sect of the family that indulged (heavily) in alcohol. It’s the groundwork for their eventual breaking from the Pentecostal lifestyle when they reached early adulthood, “Youth & Young Manhood” if you will.

While the Followill’s story is interesting with plenty of familial discourse that can be connected to the strife riddling the band currently, I feel “Talihina Sky” could use less of this footage and more of the band on tour.

The best stuff is contained there, even if it’s mostly light-hearted stoner fun among close friends/brothers. The aforementioned argument scene is the only occasion we get a glimpse at any fury between them, and it ends quickly with a heartfelt apology from Caleb. This could mean their squabbles are mostly minor and they genuinely enjoy each other’s company, but I find that hard to swallow. There’s bound to be tension here, especially given Caleb’s “Almost Famous”-esque relationship with the other three.

“Talihina Sky” will surely please KOL fans, has worthy moments with some eccentric characters (Uncle Cleo) and the home movie footage of yesteryears in a nice touch. Still, it feels a little empty, especially given recent events.