Starring Shinobu Terajima. In English and Japanese, with English subtitles. Rating unavailable

Japanese films have shown us plenty of sullen salarymen. But not that many have taken on the Loneliness of the Long-Distance Working Woman. Oh Lucy! does this in a charmingly unaffected manner, and manages to show its teeth a few times along the way.

The good-looking 95-minute feature started as a short that won awards for young writer-director Atsuko Hirayanagi. The Sundance Foundation helped her reshoot and expand her story and take it on the road. (Will Ferrell and Adam McKay are listed as executive producers.) The results have some rough edges, but the cast is so good and the story so unpredictable, that doesn’t matter much.

The camera stays mostly fixed on Setsuko (Vibrator’s Shinobu Terajima), who’s stuck in a dead-end job. The first day we see her go to the office begins with someone jumping in front of a train and ends with her oldest coworker tearily retiring. It’s pretty clear she sees both those ends as possible outcomes for her if nothing changes. In between, however, she gets a call from her spunky niece (Shioli Kutsuna), who asks if Setsuko can take over the English-speaking course she signed up for.

The “classes” are run out of a seedy love hotel. And, as played by Josh Hartnett, the teacher is unexpected too. His John is an exaggerated American, all hugs and high-fives, initially off-putting to our dour heroine, dubbed “Lucy” by John, and her only classmate, called Tom (Shall We Dance star Kôji Yakusho). But when she goes back for more free hugs, she discovers that John has gone back to California—with her niece!

Setsuko decides on the spot to follow them to L.A., and ends up travelling with her sister, the niece’s classy but controlling mother. Thus we get culture clash mixing with family dysfunction in an indie comedy that leans toward familiar quirks but subverts them at almost every turn. Not all the characterization feels thought-through; Setsuko’s tiny Tokyo apartment is crammed with stuff she never throws out, and this doesn’t relate to much else in the story. But we care about her anyway.