Letters in the Deep (Dualtone, 2010)

From their debut a few years back, Cadillac Sky has been pushing the envelope, even by contemporary standards, as far as what gets called bluegrass these days, and this third effort finds them straying farther and farther from the Monroe foundation. They've got all the standard instruments, but when a scan of the liner notes finds mention of water-phone, mellotron, harmonium and steel guitar, it's a safe bet that the music inside is not a rehash of Flatt and Scruggs classics.

And for that matter, a glance at the track titles suggests there's little to do with little cabin homes on the sunny side of the mountain: Trapped Under The Ice, Pitiful Waltz, Hangman, Trash Bag, Hypocrite and more all suggest a more somber excursion to the darker side of life. It's not, however, depressing or boring. Band founder Bryan Simpson and his mates are superlative musicians and writers, the stories hold interest, and the album is well-recorded.

It's hard to distill into a descriptive label or tag - "Americana" doesn't quite seem to fit. If a single word is necessary, "esoteric" is probably the closest approximation. Think of it as bluegrass for the adventurous.