1999 documentary about blind blues musician Paul Pena who teaches himself Tuvan throat-singing after hearing it on shortwave radio and travels to Tuva, with Christopher Nolan credited for editorial assistance.
"Christopher Nolan was credited for 'editorial assistance', being a friend of the two brothers who filmed it. It is available on Tubi for free. Both men pictured have passed on. Paul Pena on left and Kongar-ol Ondar, a Tuvan throat master, on right."