Described in some circles as the mumblecore movement's answer to the myster-thriller genre, "Cold Weather" is defiantly indie-minded—not surprising coming from writer-director Aaron Katz, the filmmaker behind 2006's "Dance Party, USA" and 2007's "Quiet City." The plot, when it comes into focus, is deceptive. Doug (Cris Lankenau) has just returned to his hometown of Portland, Oregon, and moved in with sister Gail (Trieste Kelly Dunn) after studying forensic science in Chicago. While figuring out what his career path should be, he aims low and takes a job at an ice factory. When Doug's ex-girlfriend Rachel (Robyn Rikoon) comes to town on business and starts hanging out again with their group, his new friend and co-worker Carlos (Paul Castillo) schedules a date with her. She never shows. At Carlos' urging, Doug begins investigating Rachel's disappearance and then becomes intent on getting to the bottom of her whereabouts.

"Cold Weather" is a detective story that, for a time, looks like it might be heading toward some dangerous curves as Doug and eventually sister Gail dig deeper beneath the surface of all that is not as it seems. Watching the film is like peeling an onion until it simply disappears, for, as intriguing as the narrative is, it's also a red herring. Viewers who demand clear-cut answers and movies wrapped in pretty bows will be left frustrated beyond repair by what is actually, sneakily, a story about grown siblings coming together and finding a little extra unexpected meaning in their lives. As Doug and Gail, Cris Lankenau and Trieste Kelly Dunn (2006's "United 93") are appealing and naturalistic, playing nice people who one could imagine themselves being friends with. Following them is effortless even when all they're doing is driving in a car or eating lunch on an oceanside park bench.

Writer-director Aaron Katz is exceptionally gifted in his building of a deliberate rhythm and tone that intoxicates even in its portrayal of the average or mundane. His and cinematographer Andrew Reed's lensing of a rainswept, sumptuously mysterious Pacific Northwest is just as critical to the piece's mood. What doesn't quite work is Katz's defiance in offering up very little—virtually none, actually—in the way of human drama or conflict. Yes, the mystery surrounding Rachel creates some tension, but since the movie isn't really about that, there needs to be a notable arc or some form of forward momentum within Doug's and Rachel's relationship. As is, they are brother and sister who get along famously from the start, are respectful and mostly supportive of each other, and end the film in roughly the same place. Has Doug found a new calling with his Sherlock Holmesian skills? Maybe. Will he continue working at the ice factory? If he keeps calling out as much as he does, probably not. "Cold Weather" is congenial, to be sure, but also so very subtle that it never becomes more than a confectionary dash of moody pleasantness.