Olivier Assayas’ Clean is in its way beguiling, once you survive its churning, narrow depth-of-field surface. One of those once engaging leading men content for years now to parody themselves in walk-throughs, Nick Nolte and his disheveled rasp at least try here, and succeed enough, as loving husband, grandfather, de facto father-in-law, and sane human being. (This in spite of the unintentional irony from offscreen that his Albrecht Hauser is among the movie’s few non-substance abusers.)

Technically, Emily Wang (Maggie Cheung) is not his daughter-in-law, for she and his fallen rock icon son Lee Hauser (James Johnston) never bothered to tie the knot, leaving their young son Jay (James Dennis) to grow up with Vancouver grandparents Albrecht and Rosemary (Martha Henry) while they traveled, partied, shot up, fought and downslid from rock music’s heights. Following yet another shouting match about yet another half-baked comeback chance, Lee OD’s and dies at Canada’s City Motor Lodge as she is nodding off after injecting in a car parked in rain opposite a fuming petrochemical plant. Not proved guilty of manslaughter for perhaps procuring the heroin, but sentenced to six months for possession, in prison Emily confronts her own financial and emotional bankruptcy and begins to co-compose and sing again with fellow inmate Gloria (Jodi Crawford).

When she is released, Albrecht visits, offers understanding help and, knowing his wife’s suspicious hostility to the woman, asks that she leave Jay with them. The obvious fact that no court would conceivably award custody as mother to her, anyway, goes overlooked; she agrees and, London too filled with memories of hard-living fun there with Lee, she instead returns to Paris, where musical success once loomed for her, old associates may help now, and life can be rebuilt and son Jay reclaimed. But she carries along with her a methadone addiction, and times and people have changed.

Though Emily does waitress, unhappily, in a Chinese restaurant, whose Mr. Li fires her for on-premise drug use, and is about to work in a Madame Gregory’s snobby clothing department aimed at Asian clientele, the film is commendable in making no issue whatever of race-ethnicity; the heroine happens to be a Chinese-Canadian fluent in French but is as thoroughly Western and of this shallow, hedonistic, egocentric entertainment world as anyone else. Despite the tardiness of her twinge of maternal feeling, one would like to be in her corner, but, interspersed with a couple sobbing jags, beautiful forty-year-old Cheung’s Emily is simply too stoical, even if that may be intended to imply hidden depths of feeling.

Grandma Rosemary terminally ill, the older couple flies to London for tests and a look at re-issues of their son’s albums, and Grandpa sneaks down to Paris for an unwilling Jay to get to know his anxious, grieving mother. Inconveniently, newly released Gloria insists from San Francisco, where she has secured them a one-shot golden opportunity recording session for the narrow window of that weekend only. Albrecht’s old head is wise, calm and soon to be widowered, and the final advice is his, although the closing seconds are daughter-in-law Emily’s.

To lyrics surprisingly whispered after the raucous bang of the first hundred-eight minutes, and to the sole intrusion of uncaged nature, Clean ends inconclusively. But, of course, hope springs . . .

(Released by Palm Pictures and rated "R" for drug content, language and brief nudity.)