There’s evidence of ambition in “The Yellow Birds,” a sober-minded Iraq War drama based on combat vet-author Kevin Powers’ novel.

It has a hint of “In the Valley of Elah” in its mysterious death of a soldier and Biblical undertones, of “Only the Brave” and “Stop-Loss” in its depiction of the scars veterans bring back from war.

The film attracted top-flight talent like Toni Collette and the under-employed Jennifer Aniston to play the mothers of the soldiers involved, and the New Han Solo, Alden Ehrenreich, and Tye Sheridan and Jack Huston play boots-on-the-ground, with Jason Patric signed on as a stateside military investigator looking into what went down over there.

And there’s it’s film-festival established running time, close to two hours, the length of serious drama, and bloated Judd Apatow comedies and Marvel movies.

But for all the vivid combat sequences, the gritty adjustment-back-home touches and a couple of genuinely emotional scenes, it feels incomplete, choppy and something of a cheat. Blame the screenplay, which shortchanges and over-sells its mystery, and the attempts at whacking the thing into releasable shape. Few pictures can cling to coherence after losing more than twenty minutes of run time, especially films which were cut for cause.

Ehrenreich and Sheridan (“Ready Player One”) are green Virginia boys who meet at boot camp. One may have enlisted because he’s adrift and the other as a life-experience craving artist planning on attending the University of Virginia afterwards. But their connection is a necessity.

Sergeant Sterling (Huston, of “Boardwalk Empire” and the recent “Ben-Hur”) ordains it. They’re to keep an eye on each other and “promise you’ll do what I say every f—–g time,” and they’ll be fine.

Private Bartle (Ehrenreich) is given further orders by Private Murphy’s mom (Aniston).

“Promise me you’ll take care of him over there.”

We don’t need to hear the film’s opening narration, that “The war tried to kill us in the spring, and the summer…It tried to kill us every day” to know that dramatic “take care of him” cliche will have its consequences.

Through the ambushes, the IEDs and the firefights, French director Alexandre Moors (the extraordinary “Blue Caprice” is his biggest non-music video credit) fails to get across the promises made and the sense that these guys are bonded and truly looking out for each other.

Except in the unit dance party, where Bartle urges Murphy to dance with a medic he’s got a crush on.

The combat sequences have the requisite fire and fury and gulping, weeping fear. They feature the usual incidents such movies inevitably include — a Humvee blown up by an improvised explosive device, a party interrupted by a mortar barrage, snipers who kill comrades and are then hunted down and killed, accidents in the heat of a firefight.

Something happened that shouldn’t have. That much is obvious when they get back home. One man is missing, others are cracking up and the Army’s sent an investigator (Patric), not a shrink, to help them cope.

Collette anchors this home front section of the film, an angry single mom who wants the Army investigator to answer her question first.

“What’d you people DO to him?”

Aniston manages a sympathetic portrait of a parent looking for answers to her questions, as well.

And Huston stands-out among the foot soldiers, bellowing orders in a nearly indecipherable drawl, blowing off the investigator with a beautifully bitter “I ain’t nobody’s sergeant no more.”

Ehrenreich is sympathetic and more suited to this role than the future-swaggerer Han Solo, but he’s still not a charismatic screen presence to hang your picture on.

It’s the film in toto that stumbles, a bungled march of fits and starts, scenes that  work as stand-alone moments, but connect more in our memories of the tropes of combat films than in anything the director and screenwriters manage.

The drastic editing can’t have helped in terms of coherence. Any explanation of “The Yellow Birds” is lost as the titular metaphor (and military marching cadence) that inspired it is the 20 minutes or more they whacked from this.

There have been too many good, bad and indifferent movies about the Iraq War to waste your time on a mediocre one, especially if there was probably a good movie in the book this one is based on.

MPAA Rating:R for war violence, some grisly images, sexual material, and language throughout

Cast: Alden Ehrenreich, Jack Huston, Jennifer Aniston, Tye Sheridan, Toni Collette, Jason Patric

Credits: Directed by Alexandre Moors, script by David Lowery, R.F.I. Porto, based on the Kevin Powers novel. A Saban Films release.

Running time: 1:35