One of my mentor teachers, Chitresh Das, is the subject of a documentry about improvisation and a collaboration with an award winning tapdancer.
The title Upaj, means a musical expression that arises spontaneously and instantaineously from the heart.
It is showing on PBS today, tomorrow and next monday. PBS is a government station so it is anyone's guess when it is actually showing. This page is supposed to tell you.
Commentary to follow when I actually watch it. But it will be amazing I'm sure.