Downview Prison in Sutton, England, is an enlightened institution, if only by evidence of director Hill's project, in which various inmates are filmed telling their often horrid stories, the essential emotional truth of which is set in songs sung by the women themselves.

The film succeeds partly because of its unusual technique (although Hill has worked a similar mix in such films as "Drinking for England"). Through the musical numbers, "Songbirds" achieves an artistic and emotional clarity that all the talking-head interviews in the world could never produce.

The songs by poet Simon Armitage and composer Simon Boswell are infectious hybrids of various pop musical genres, with which the women's particular vocal talents are superbly matched. That the women possess such voices is remarkable. Maggie, for instance, a former crack addict who lost her children to social services, has a keen Irish alto that she could easily parlay into a career. Doubly remarkable is that Hill didn't select them for their voices, but for their stories --stories that all share a thread of sexual abuse, which helps turn what seem like otherwise ordinary women into criminals.

Class, too, is an issue. Theresa, whose more upper-class accent distinguishes her from fellow inmates (as does her crime), is the exception that serves the rule --that prison populations in England and elsewhere are made up of the economically deprived.

But "Songbirds" is hardly a downer. Watching the women perform the numbers they've been given is joyous. And if a movie can elevate its subjects to such emotional heights while working similar magic on its audience, there seems little to do but applaud.

Camera, (color, HD), Michael Timney; editor, Stuart Briggs; sound, Marc Hatch, Simon Parmenter. Reviewed at Sundance Film Festival (World Cinema, competing), Jan. 22, 2006. Running time: 80 MIN.