It's impressive that, after 10 years as a project, Let Spin are still finding fresh ways to develop their ideas without losing the band's distinctive identity. Thick As Thieves is practically a concept album, inasmuch as the 10 tracks segue through without a break and musical motifs and ideas slip in and out of focus across its flow.

There's a fairly constant tempo but distinct mood shifts – sometimes dramatic, other times more nuanced – which give the individual ‘tracks’ their character. As with their three previous albums, compositional credits are spread across the four musicians but with more fluidity, and the overall sense is of them working to a collective understanding of how the band should sound through improvisation. This can mean simple four or five note phrases tossed between instruments (as in the high energy track 'Mixed Messages') or long and complex melodic lines coalescing from two voices in the scattershot 'Broken', 'I Told You' or the more spaciously ambient 'North Sea Swim'.

Naturally there are moments of prog heaviness – 'Mixed Messages' boils down over a frenetic bass riff, 'Bead' builds from the chattering Morse Code bass of the previous track into an epic theme that dissipates into 'Liminality', the tight and assertive final track. Listening straight through the album feels like a journey across a post-rock landscape full of comfortable surprises, with 'Liminality''s resolute Ayler-ish coda marking an inevitable and satisfying destination.