This 8CD box contains seven full live sets from two nights’ work by the quintet of Davis, saxophonist Wayne Shorter, pianist Herbie Hancock, bassist Ron Carter, and drummer Tony Williams. Every member of the band was committed to challenging themselves and the others, changing harmonies, tempos and dynamics on the fly and doing the unexpected at virtually every turn, charting a path between ultra-high-level hard bop and free jazz without calling it that. Despite containing versions of songs he’d been playing for years, this is some of the most avant-garde music in the Davis catalog.