It’s been more than two years since France’s Chaos Echoes released their debut full length album, “Transient,” which showcased the band’s deft navigation among labyrinthine channels under, around, and through the outer reaches of the extreme metal genre. “Transient” established Chaos Echoes as one of the most compelling and innovative groups of musicians in the scene, and anyone who has witnessed some of their live performances since that time, such as their flawless presentation at NWN! Fest in 2016, has likely been appropriately awestruck by the band’s skill and dynamism. Listeners may recall that interspersed throughout the “Transient” album were improvisational pieces, referred to as “Interzones” (a nod to Burroughs’ “Naked Lunch”), that provided connective tissue between the more heavily constructed songs on the album. Similarly, “The Unfathomable” may be regarded as an Interzone between the aforementioned “Transient” album and Chaos Echoes’ forthcoming full length, entitled “Mouvement,” which will also be released on NWN! Productions.