Few more exposing formats exist for free improvisation than the saxophone and piano duo. The stubborn inability of the equal-tempered, eight-notes-to-the-octave piano to bend pitches and actively alter the timbre of a note once sounded throws up a peculiar set of challenges which don't apply to malleable wind instruments or drums. In this set of duo improvisations with Trevor Watts, Stephen Grew solves that problem, like many free improv pianists, by incorporating the inside of the instrument into his concept – but few pianists manage to integrate keyboard and inside so seamlessly, the latter never registering as an ‘effect’. ‘Bird's Eating’ begins with Watts slapping notes with his tongue as Grew dampens the notes he's sounding on the keyboard from inside the piano which generates a mirage of echoing tones and shadows from which the improvisation spills out. And they can groove, too. The opening piece, ‘Shepherd's Return’ hurtles forward with a tightly controlled sensation of dissipating swing. Occasionally – like at the end of ‘Bird's Eating’ – Grew defaults to treating water by rotating patterns, while Watts opens up the harmonic terrain. But sometimes that's All There Is.