In 1991, a loose-knit collective released a record called Blue Lines under the name Massive Attack, splicing together American hip-hop and soul with the sounds of the British underground. With its marauding bass lines, angular guitars, and psychedelic effects, Blue Lines built on the Caribbean soundsystems and nascent rave scene of the 1980s while also looking ahead to the group's signature blend of epic cinematics and lush downtempo...