THE RECENT Botox revolution prompted one wag to observe that while youth may be wasted on the young, it looks ridiculous on the old.

No Botox, thank heaven, in "Away From Her," an end-of-life drama featuring Julie Christie as a Canadian woman named Fiona succumbing to dementia. The heart of the drama is the impact of the advancing disease on her 44-year marriage to husband, Grant (Gordon Pinsent), and "Away From Her" wouldn't make any sense if you couldn't see all of those years reflected in Christie's face.

It's a stroke of casting genius, really, - it's not just Grant who fell in love with Christie 40 years ago, it's just about every guy who saw her in "Dr. Zhivago" (shots in "Away From Her" of Christie in a snowy wilderness invite those references).

Moviegoers of a certain age have their own long history with Christie, and when we look at her we see some of what Grant sees - the outline of the beauty she was in her 20s, filtered through 40 years of time that confer the poignancy essential to this story.

The movie is a collage of flashbacks, through which we understand that Fiona and Grant have a great marriage, foremost because it wasn't always great. Director Sarah Polley is not yet 30, an age when many directors portray marriage (if it doesn't end in divorce) as a fraud, a loveless compromise.

But Polley, borrowing from a story by Alice Munro, and maybe some of its wisdom, gives us more. Here, time rewards compromises and commitment to a flawed arrangement, and we get a rare portrait of the intimacy that can come with endurance.

Certainly we get past Hollywood myths about perfect compatibility and romantic destiny. Fiona gives a biting speech about the "liability" of that kind of naive thinking, and Christie delivers it beautifully.

Polley's impressionistic structure allows her to contrast Fiona's crisp lucidity with her increasingly frequent bouts of blank terror - we understand why she has to go to an assisted-living facility, alone, and why it crushes Grant (Pinsent is terrific).

What makes this a tragedy, not a movie of the week, is the way Christie is able to suggest varying levels of awareness. This is crucial to narrative, which has Fiona adapting to her rest home by forming an intense relationship with another man (Michael Murphy).

Grant wasn't always faithful, but he's fiercely so now, and he recognizes devotion means accepting that Fiona has ceased to understand her old world, her life with him. Her happiness now rests entirely on her new attachment, and he must fight for that.

The portrait of the rest home is vivid and fair, with Grant chafing at the officious administrator even as he is helped informally by a compassionate nurse. It's also often humanely funny - one patient is a hockey announcer who doesn't realize he's retired, and provides play-by-play for all events at the home (even heartbreak), a device that is used ingeniously. *

Produced by Daniel Iron, Simone Urdl and Jennifer Weiss, written and directed by Sarah Polley, based on the story by Alice Munro, music by Jonathan Goldsmith, distributed by Lionsgate.