"The Iron Lady" isn't the cinematic hit piece conservatives expected when they first got word of the Margaret Thatcher biopic.

Instead, it's something both better and worse. "The Iron Lady" celebrates Thatcher's resolute spirit and ability to smash the political glass ceiling into so many shards. The film also spends an inordinate time with Thatcher in her later years, a time when the older woman was coming to grips with her diminishing mental faculties.

[youtube mf5qHuRJG1Q nolink]

The combination is so jarring it's hard to properly assess the film's merits. Yet there's nothing unclear about Meryl Streep's magnificent performance as the conservative icon. Streep's career may be chockablock with precision tuned accents and flowery roles, but it's still a revelation to watch her become Thatcher before our skeptical eyes.

"The Iron Lady" begins in a humble grocery store as an aged Thatcher looks to restock her home's milk supply. The outing wasn't what her friends and family had in mind. They'd rather the old woman stay at home where she is safe.



We then experience one in a series of flashbacks tracing the arc of Thatcher's remarkable rise to power. We meet a 20-something Thatcher (winningly captured by Alexandra Roach) and discover the roots of her indomitable spirit. Thatcher is wooed by a lad who would become her loyal husband Denis (later played by a jovial Jim Broadbent), and through a series of events she finds her political voice.

From there it's Streep's turn to show us Thatcher at the height of her powers, bowling over those eager to dismiss her for being a woman and others who simply disagree with her conservative principles.

Director Phyllida Lloyd ("Mamma Mia!") isn't the obvious choice for a political yarn, but Lloyd invests "Lady" with a power and grace that command your attention, ideology be darned. By the time Thatcher is ready to roll up her sleeves in parliament - but not willing to forgo her signature pearls - "The Iron Lady" crackles with an intensity rarely seen in Oscar bait features.

Every time the film feels primed for greatness, we're pulled back into the aging Thatcher's world and must suffer though more imaginary conversations between her and her late husband. Here, Thatcher converses with Denis as if he was still alive, even though it's been years since he had passed on.

Focusing on the doddering old Thatcher might seem the height of cruelty, but Lloyd and company treat the subject with respect. That doesn't make the storytelling structure any less rickety. Why in the world should we see Thatcher's story through such an unflattering, and gauzy lens? It's one of the most confusing, and ill-suited, framing devices imaginable for a biopic. It might have made sense if "The Iron Lady" was an unabashed hit piece, but that's clearly not the case. The film even allows Thatcher to serve as a feminist ideal, a woman who refuses to bow down to societal pressure.

"The Iron Lady" serves up a greatest hits montage of Thatcher's political reign. And just when you think the film is ready to sink its teeth into some of her many accomplishments, the story starts steering itself toward the final credits.

Streep keeps us engaged even when we're forced to watch Thatcher struggle for idle chit-chat during a verbose cocktail gathering. It's a towering performance in search of a consistently great movie, something "The Iron Lady" delivers in teasing flashes.