Something more than a child goes missing in Clint Eastwood's "Changeling," his tale casting Angelina Jolie as a real-life single mom whose young son vanishes in 1928.

On the surface, "Changeling" has all the rich atmosphere and evocative detail of his recent Academy Awards offerings, "Mystic River," "Million Dollar Baby" and "Letters From Iwo Jima."

Yet it lacks the emotional depth and nuance of that string of films marking Eastwood's remarkable late-career resurgence. Instead, "Changeling" slips back toward the workmanlike storytelling of Eastwood's decade between "Unforgiven" and "Mystic River" -- sturdily made movies that ranged from passably engaging to completely forgettable, and mostly hollow at heart.

With his first foray into heavyweight drama, TV writer J. Michael Straczynski (creator of the sci-fi series "Babylon 5") crafts a meticulous screenplay centred on the case of Christine Collins, who became a victim of nightmarish persecution by corrupt Los Angeles police handling the case of her vanished boy.

As the story grows bigger and more horrific, Eastwood and Straczynski lose focus, their sharp portrait of a mother facing the worst possible loss swallowed by a scattered, one-note melodrama of a lone saint battling a den of demons.

Jolie's Christine is an angelic figure, a woman making a safe and comfortable life on her own for herself and nine-year-old son Walter at a time when single-parent families were more of an anomaly.

One day, Christine returns home from her job supervising telephone operators to find Walter gone. Five agonizing months pass without a clue, and then police notify Christine that her son has been found.

Amid a media circus, police Capt. J.J. Jones (Jeffrey Donovan) presents a boy that Christine insists is not Walter. The unctuous Jones convinces her to take him home anyway to try him out and see if perhaps, given her emotional distress, her own memory had failed.

With help from a social activist and radio preacher (John Malkovich), Christine mounts a crusade against the monolithic police department, whose thugs and scoundrels brand her an unfit mother trying to duck out on her obligations.

From there, "Changeling" broadens into horror stories running on separate but parallel tracks, city officials going so far as to lock Christine up in a savage nuthouse, while clues to Walter's fate turn up on the chicken ranch of a serial killer who slaughtered children with an axe.

The film rolls rather ploddingly through awful deeds and terrible revelations. And while the real story of Christine Collins abounded with loose ends, that does not make the fitful and protracted wind-down of "Changeling" any more satisfying to watch.

"Changeling" is a fine piece of technical craftsmanship, loaded with period flourishes that make L.A. in its early decades come alive.

Yet it all just seems like window-dressing for Jolie's best-actress clip at the Oscars. It's a fine if repetitive performance, but she's already done the woman-in-the crazy-house thing with her Oscar-winning role in "Girl, Interrupted," and she was better in last year's "A Mighty Heart," which failed to land her a nomination.

Amy Ryan, an Oscar nominee as the mother in a missing-child case in last year's "Gone Baby Gone," has a few strong moments in a fleeting role as one of Christine's fellow psych-ward inmates.

And Malkovich, who co-starred with Eastwood in "In the Line of Fire," is engaging and compassionate in a rare heroic role.

Donovan and other key players, including Colm Feore ("Trudeau") as the black-hearted police chief, are so utterly despicable they become caricatures. Eastwood might as well have given them bushy moustaches to twirl as they plot their next act of evil.

There's nothing wrong with old-fashioned storytelling where good and evil are clearly delineated, but next to the moral complexity of Eastwood's recent films, "Changeling" comes off as a great expenditure of cinematic prowess in service of simplistic drama.

Two stars out of four.