Fiddler/singer Alison Krauss is a phenomenon in that she's a child prodigy (started playing at 5, recording at 14) who's achieved a substantial measure of mainstream success by performing purely acoustic music: traditionally oriented bluegrass with folk overtones, occasionally adapting distinctly "outside" material to her style (e.g., songs by the Beatles, Bad Company, and Shawn Colvin). Lonely Runs Both Ways continues along the same high standards as her previous albums, with a few notable exceptions: There are no well-known cover choices, no breakneck-paced, "Orange Blossom Special"-type tunes, and Krauss' gorgeously dulcet singing has acquired deeper, more poignant dimensions. The impassioned quaver she musters for the line "I don't know that I will ever trust again" on "My Poor Old Heart" almost gave me chills. Fear not, all is not gloom -- the exhilarating instrumental "Unionhouse Branch" showcases Union Station's fab chops, especially Jerry Douglas' keening, blues-tinged dobro, while nodding toward bluegrass' Irish roots. Not merely a superb work, the aching Lonely may well be Krauss' very own "Songs for Shattered Lovers" concept album.