Tortoise have always emphasized their connection to Chicago, and never more so than on The Catastrophist. Arriving six years after Beacons of Ancestorship, its roots date back to 2010, when Tortoise were commissioned to write music inspired by their hometown's jazz and improvised music scenes. Though they fleshed out those compositions for the album, the original project's sense of adventure remains. Fittingly, the title track has some of the closest ties to the album's beginnings, holding together shifts between knotty, busy electro-funk and the kind of brooding post-rock Tortoise helped define in the '90s with nimble drumming indebted to jazz. "Shake Hands with Danger" is even more audacious, nodding to the Windy City's free jazz and noise rock legacies with jabbing riffs and rhythms and chromatic percussion that sounds metallic in both senses of the word.