I can’t remember the last time I had so many “Wait, what?” moments watching a film as I did during the deeply uninteresting “Nostalgia.”

What we are dealing with is a theme without a story in a film working overtime to be compassionate and heartbreaking.

From its scattered narrative to its morose musical score to its borderline criminal misuse of a talented cast, it is a clear front-runner for next winter’s Worst Films of 2018 list.

Skipping between a half-dozen scarcely related vignettes, it studies how the passage of time turns one person’s possessions into another generation’s beloved heirlooms or grist for the Dumpster.

The opening episode gives us Bruce Dern as a selfish codger not much interested in passing any of his belongings to his estranged granddaughter (Amber Tamblyn).

Dern plays crusty old coots as well as anyone in the business, but the background on his lonely golden years is unexplored.

The insurance appraiser who serves as their go-between (John Ortiz) then moves on to help wet-eyed, verbose Ellen Burstyn deal with the few valuables she rescued from her burning home.

Of course, the real value is the emotional worth of a baseball memento that was prized by her late husband but meaningless to her.

Oh, the bittersweet irony of it all.

Then Ortiz wanders out of focus and the saga’s bouncing ball careens into “Come again?” territory. We enter passages featuring such fine talents as Catherine Keener, Nick Offerman and, if a 15-second cameo walk-on counts, Patton Oswalt.

It’s all intensely concerned about holding onto the past or losing that connection, which seems to be the only topic these people ever talk about.

This is not a matter of wide concern, is it? Those who shuffle off, leaving their material goods behind, are past caring much about knickknacks.

If the survivors rely on Grandma’s Hummel figurines to remember her, they weren’t deeply connected in the first place. Unless there’s a hot secondary market for all that stuff, who cares, really?

Well, director Mark Pellington and screenwriter Alex Ross Perry want you to know they care very deeply.

“Nostalgia” seems unable to decide who it’s about, what it’s about, or who it’s for, but it ponders its characters’ collections of curios with the demented focus of a hoarder on leave from the sanitarium.

Though all the actors bring a sense of authenticity to their craft, they’re burdened with overwritten, poetic speeches that would work much better on stage.

Jon Hamm, winning the film’s Most Valuable Player Award as an experienced Las Vegas collectibles dealer, declares “everything is trash, or will be.”

That’s an insight the filmmakers should have taken to heart, rather than exploring an insignificant idea through random chapters of self-important melodrama.