Jabbing and weaving around the medical, legal and political underbelly of 1920s Los Angeles, Changeling is a sprawling epic from director Clint Eastwood. Ultimately too unwieldy — and with shameless, strange Oscar-baiting — to be considered an Eastwood masterpiece, it’s peppered with minor brilliant flourishes.

Chief among them is Angelina Jolie’s lead performance — the second biopic in two years (A Mighty Heart) in which she grieves for a likely dead member of her family.

Unlike the journalistic doggedness of Mariane Pearl — widow to slain reporter Daniel Pearl — Christine Collins’ composure comes from a powerful place of maternal, and social, persistence.

Christine is consistently heroic in pursuit of her kidnapped son. With a skeletal and frame, pale-and-flat skin, a stirred-not-shaken tone of voice and sunken face swallowed by those smackers, Jolie affirms this allegiance easily and early.

However, it’s the way screenwriter J. Michael Straczynski elicits Christine’s erstwhile social crusade that tells a resonant tale of social activism.

Christine is a single mother to Walter (Gattlin Griffith), working as a supervisor at a telephone-operator station. Production designer James Murakami sprinkles in memorable details like Christine gliding on roller-skates around the room and insets of Indian motorcycles.

Returning home from a last-minute shift – a day on which she was to take Walter to the movies – Christine finds Walter gone. Panicked, she calls the police, who promptly delay her missing-persons claim. Her crisis draws the attention of Rev. Gustav Briegleb (John Malkovich), an outspoken critic of police corruption.

Eventually, Walter’s rescue is seen as positive PR for a department wheezing with sickness, and Captain J.J. Jones (Jeffrey Donovan) makes it a priority. Donovan barks his lines in a patchy brogue and clinches his face up like a Dublin Clint, but Straczynski captures infectious aspects of adhering to a knowingly false narrative.

That’s because the child returned to Christine isn’t Walter. This kid is tight-lipped, flashing odd smiles at everyone and, most damningly, shorter in height. Regardless, Christine’s protests land her in an asylum for women — where she must tread the careful line between sanity and madness to avoid a lobotomy.

Eastwood works at cross-purposes against Jolie’s measured composure in this setting – someone wailing in every single scene when silence could have deafened.

It’s also where the film starts to lose its grip, dovetailing with the pursuit of Gordon Northcott (a frighteningly deranged and dissociated Jason Butler Harner) — a child killer whose empty gleam predated Charles Starkweather.

Plots predictably intersect, Malkovich is reduced to genial and gentle exposition, and there are three denouements too many, including one in which it seems a contest to mention the Oscars as much as possible. Also, can someone get Eastwood an orchestra? Mournful guitar lines he writes as a composer are incredibly played out.

Still, Eastwood and longtime editor Joel Cox deliver an emotionally draining interrogation scene. It lacks the star power and attitude of Tim Robbins, Kevin Bacon and Laurence Fishburne in Mystic River, but it’s integral to the film’s macabre mood. As, respectively, a Northcott accomplice and skeptical detective, it’s harrowingly acted by young Eddie Alderson and Michael Kelly.

Changeling is not quite as tough-minded as L.A. Confidential, and a lot more manipulative in its tale of crisis and prejudice. But its burnished look and icily chilling moments establish it as a polished period epic in that vein.