"Mermaid" is the darkest song you'll hear all year: a self-contained fable shot through with evocative and disturbing imagery but rising to a sweeping, romantic, oddly moving climax.

This waltz-time ballad gestures towards the tattered folk of OKKERVIL RIVER's beloved 2005 album "Black Sheep Boy", but somehow unearths something much more mysterious and blurrily ambiguous.

With "Walked Out On a Line" we get a glimpse of what might further emerge. Choral and atmospheric and stripped of any of the acoustic textures that have defined much of the band's past work, "Walked Out on a Line" is a smooth-sailing symbolist fever-dream, fractured and impressionistic lyrics floating over a sea of sighing voices, glittering rhodes, and a gently driving beat.

It's an ambitious statement about how much innovative fuel the band has to burn, an as fleeting a 5:20 song as you're likely to hear.