This stellar two-CD set documents Keith Jarrett’s Scandinavian quartet at the peak of its creative and interactive powers. Comprising previously unreleased recordings from a concert at Tokyo’s Nakano Sun Plaza in April 1979, it explores the delicate space between composition and pure improvisation, with Jan Gabarek’s pungent tenor sax and Jarrett’s inspired piano runs dancing joyously on top of the Palle Danielsson- Jon Christensen rhythm tandem. The opening “Personal Mountains” is a 20-minute tour-de-force that has the quartet in all-out energized mode for a full 15 minutes, with Jarrett’s aggressive chordal stabs setting the tone, before segueing to a calming, introspective section that Garbarek blows over with deep, penetrating tones. “Innocence” opens with a spacious, rubato duet between piano and sax before resolving to Jarrett’s achingly lyrical theme for the full band. Garbarek delivers some of his most beautiful, vocal-style playing on Jarrett’s warmly engaging “So Tender.” The adventurous 28-minute “Oasis” opens with Jarrett laying down a percussive pattern on African slit drum while Garbarek wails on wood flute. “Chant of the Soil” is imbued with Jarrett’s signature funk-gospel feel while “Prism” is a luminous gem that highlights the uncanny conversational élan of this remarkable quartet.