Few artists are in such vibrant dialogue with those twin impostors, rigour and imagination, as Mary Halvorson. Practice, practice, practice, then wail, exhorted Charlie Parker, and there's something equally seductive in Halvorson's ability to sound so insouciant and unpremeditated, when in fact every song has a bear trap structure expressed through giddying technique.

Artlessly Falling meditates on poems written by Halvorson that have a particular metric shape. So ‘Lemon Tree’ is a tanka (a 31-syllable Japanese one- liner), the title track a sestina (six verses of six lines, but, heh, that's only the beginning), and, for fans of Jodie Comer, there's a villanelle (think Dylan Thomas' ‘Do not go gentle into that good night’).

But of course, you need know none of that to revel in this oh-so-beautiful album. The core band for this second Code Girl release, is augmented by Maria Grand's sax and voice and O'Farrill's horn. But the real coup is Robert Wyatt's voice on three songs. His first major musical contribution since his 2014 ‘retirement’, his voice is more vulnerable yet more expressive for it. Wyatt's influence has long been apparent in Halvorson's work (along with the likes of Carla Bley) so to hear them together is a natural consummation.

This also gives Halvorson three voices to create different textures, which she does deliciously.

Like the best art, Halvorson leaves the listener to bring their own interpretation, whether it be to the neurotic blues of ‘Last Minute Smears’, or the Dave Douglas-tinged ‘Muzzling Unwashed’ (great trumpet from O'Farrill.) Artless? No, and falling? Definitely not! This is uplifting as only the best can be.