Let Them Say is the first fully instrumental album by Notturno Concertante, described by the band as "ethno progressive rock". It has eleven tracks, including "Finis Terrae", "Delicate Sabbath", "Darkness I Became" (for solo piano), "Fellow Travellers", "Dei Miei Sospiri" (which incorporates parts of a madrigal by Carlo Gesualdo, performed by the Gesualdo ensemble), "Lovers Second Leap" (originally conceived as a coda to a Genesis piece the band often performs with Ray Wilson), "Le Magnifiche Sorti (e Progressive)", "So Far Out", "Handful of Hopes" and "Evidence of Invisible". The album combines acoustic instruments and electronics, with folk, jazz, blues and neo-prog elements. Guests include violinists Molly Joyce and Nadia Khomoutova, cellist Kaitlyn Raitz, clarinettist Rappa Shokai (Seto Nobuyuki), drummers Francesco Margherita and Simone Pizza, and bassists Luciano Aliperta and Giuseppe D'Alessio. The band's live and recording collaboration with former Genesis singer Ray Wilson is also noted.