Starring: Samantha Morton, Kathleen McDermott, Raife Patrick Burchel. Not Rated.

Morvern Callar comes home one day to find her lover's lifeless corpse lying beneath the Christmas tree. Having slashed his wrists because, he says in a note, "it just felt like the right thing to do," he has left her a few gifts under the tree, a cash card and his unpublished manuscript.

From there, a dazed and confused Callar (Samantha Morton, last seen in Minority Report) embarks on an amoral adventure with her party pal, Lanna (newcomer Kathleen McDermott), bankrolling her escape from a dreary Scottish port town to an exotic Spanish resort with money lifted from her late boyfriend's bank account. When that money runs out, she passes off the manuscript as her own, earns a quick £100,000 from a British publishing firm, quits her job at the local supermarket and continues her travels.

What is Morvern searching for? That's never clear. To be sure, she gobbles up her boyfriend's cash and intellectual property, but she is hardly motivated by greed. And while it's hard to accept that his suicide would go unnoticed -- and even harder to accept Morvern's decision to chop him up and bury his remains in the desolate countryside, a la Tony Soprano -- it's surprisingly easy to sympathize with her emotionally crippled protagonist.

Her choices are ethically dubious, but they seem borne more out of a perpetual state of shock than true cold-bloodedness. Morvern Callar, after all, is the story of a woman who wanders through life in a daze, concealing emotional turmoil beneath her blank, expressionless surface. She's searching for something, and whether it's passion, power, sexual satisfaction or merely the freedom to escape her dreary, painful existence, she is bound to her quest, wherever it leads.

The quest is compulsively entertaining, as Morvern's journey unfolds in unpredictable, stream-of-consciousness fashion. Theres spontaneity and danger in her every move, and it's easy to follow her adventures, with bated breath, to their uncertain conclusions. And though critics have understandably described the film as bleak -- perhaps due to cinematographer Alwin Kuchlers decision to shoot the film in muted tones -- there is an uplifting quality in Morverns liberation from her dead-end job, her run-down apartment, even conventional notions of morality.

Morton infuses the title role with the right mix of bewilderment, strength and suppressed agony. Hers is a conflicted heroine whose emotions are volatile and her direction unclear. Morton's haunting brown eyes convey those emotions as well as her actions do; at first, she is stricken with fear and uncertainty, but as she becomes more composed and self-assured, gradually regaining control of her tumultuous life, Morvern evolves into a picture of steely resolve.

Even so, Morvern Callar offers little in the way of resolution.

In the end, the protagonist keeps wandering, her search for fulfillment having yielded nothing more than a few fleeting thrills and a tantalizing glimpse of the future. It's a fitting conclusion, if not the most illuminating, for a film that's always compelling, even when its pace is a bit sluggish.

It's also a breakthrough triumph for Scottish director Lynne Ramsay (Ratcatcher), whose fourth film benefits not only from a strong script (based on Alan Warner's novel) and one virtuoso performance, but also from a wonderfully eclectic soundtrack featuring Aphex Twin, Ween, the Velvet Underground and Nancy Sinatra. -- Rossiter Drake