Floating ethereal melodies, cloudy vocal lines and other-worldly soundscapes are what we've come to know of Alcest: the French post-rock project of ex-Peste Noire and Amesoeurs guitarist Neige. Whole-heartedly focused on concept and imagery, Alcest has always been about staging in musical form a complex idea or a fanciful story, delicately painting each note on a canvas of silence to reveal a magical realm like that of 'Fairyland'; Neige's affectionate name for the nostalgic inner-place he visited during his childhood. And, for his last two releases - Le Secret (2005) and more notably, Souvenirs D'un Autre Monde (2007) - he has more than succeeded in recreating the glittering streams, luminous landscapes and esoteric beings he's described as having appeared there.

Now on full-length number three - Écaille De Lune - the image has started to blur. Long gone are the fantasies and the hope and the innocence, to be replaced by the disappointment of mundane adult life, the disillusionment of human relationships and the wistful abandon of childhood dreams. Shades of ochre and warm terracottas have been replaced with deep, tumultuous tones of cobalt and charcoal as Neige attempts to tell a more sorrowful tale about a man so tired of life as he sits in front of the sea at night, that he swims out into the waves and drowns to free himself of his worldly depression. And though the medium remains familiar – the same floating post-rock melodies are all here - there are, quite appropriately, melancholy forces at work, complimented by rushing crescendos, sampled sea-sounds and weightier, more dramatic guitar sections.

Those who are aware of Alcest's original form as a three-piece black metal outfit [hear 2001 demo 'Tristesse Hivernale'] may be tempted to interpret these 'new' elements as a nod towards a darker past. But the only real glimmer of anything vaguely sinister is the presence of tortured, screaming vocals on two tracks out of six, and the odd bit of tinny snare. Black Metal fans wishing for anything more pounding will be sorely disappointed: it's about as extreme as a micro pig (small but mighty, one might argue). For everyone else, this is an intricate, beautiful, burgeoning classic and an absolute must for any self-respecting alternative record collection.