The late Tom Sizemore’s waning days and only slightly-diminished talents were utterly wasted on “Impuratus,” an under-lit, under-edited and over-written period piece mystery just now coming before the public.

It’s a supernatural thriller about a 1920s detective summoned to hear a “confession” from an ancient, near-catatonic Civil War veteran, played by Jody Quigley.

What the film — whose title translates as a succint two-word review, “vile, infamous” — adds up to is a 35 minute dramatic short spread over 133 minutes of run time. It’s interminable, with scene after pointless scene and a novella’s worth of discardable, doesn’t-advance-the-plot-or-illuminate-characters dialogue.

Sizemore’s Allentown police detective gets the word that a witness to all this man’s weird history is dead, but only after he’s been informed of much she said and thought, ad nauseum, by the head shrink (Robert Miano) at a Pennsylvania insane asylum.

“Passed. Whattaya MEAN passed? As in dead? AS IN DEAD?”

That’s a lot of words to get across “Oh she’s dead, is she?”

“Well well well, that’s a fascinating surprising development, Doc.”

Well, if you say so, flat foot.

Writer-director Mike Yurinko burns through some 20 minutes of screen time just to get us to the point where our detective is summoned to that mental hospital — by the patient — only to be trapped there A) by a coming ice storm and B) by this endless back-story, some of it visited in Civil War flashbacks, much of it narrated from combat veteran Daniel Glassman’s jumbled, run-on “All work and no play makes Jack a dull boy” typewritten confession.

Sizemore was perfectly credible as a detective, private or police, in most periods the movies depict such gumshoes.

“People say the damned things to avoid getting what’s coming to him,” he growls, and we buy in.

But he floundered here, a troubled actor and screen veteran who seems to realize what he’s saddled with here, and that no amount of improv or animation on his part can improve it.

Yurinko (“Entity” was his) made a dark, not-particularly spooky movie that is cryptic with no real mystery to hide, repetitive with no scene or situation worth repeating and based on a script that apparently he got no feedback on before starting production.

“What causes mental illness?” our pre-Freudian detective wants to know at one point. That’s what we call a non-starter.

And “Just get to the point” he says later, one instance where he really should have repeated himself — constantly. Not that one line, even repeated, would have made a difference in this dull exercise in demonic whaeverness.

Rating: unrated, violence, some profanity

Cast: Tom Sizemore, Robert Miano, Airen DeLaMater, Lew Temple,
Silvia Spross and Jody Quigley,

Credits: Scripted and directed by Mike Yurinko. A Gravitas Ventures release.

Running time: 2:14