After two well-received LPs, Finland's obscure but habitually excellent Red Moon Architect returns with their latest: Return of the Black Butterflies. Armed with a new vocalist, Red Moon Architect's sound has gotten heavier and more atmospheric than ever before.

The basic elements of the band's melodic doom metal sound, a study in contrast between delicate piano, creepy music-box tinkling and crushing guitar riffs, remains the same. Ominously echoing clean picking offset the vocals of Ville Rutanen, an utterly indecipherable cross between a growl and a croak, which however get second billing to the voice of Anni Viljanen, who does the female vocals. Sure, "Beauty and the Beast" goth-metal duets are a genre trope by now, but Rutanen makes for an especially brutal Beast, and Viljanen an especially despairing Beauty. Without an operatic style, Viljanen's plain, clean (if slightly nasal) vocals are more effective than they would be otherwise.

Despite the slow speeds and atmospheric effort Red Moon Architect puts into its songs, there's a variety to them that keeps the listener interested. The funereal waltzes of songs like Journey, where Viljanen puts in a solo performance, contrast very nicely with NDE, a thunderous finale of dragged-out chords on top of a ghostly piano, buried back in the mix. Listeners to Draconian and Trees of Eternity should give this one a try.