A vintage 1976 documentary made by Norman Mailer about the early years of the graffiti scene in New York City, it followed a book by Mailer of the same name. The filming is approached with a neutral perspective, giving camera time to both graffiti artists and members of the community who hated seeing their local streets constantly vandalized.
This is not the only old documentary to explore the early street art movement in New York, in 1983 the now legendary documentary Style Wars was aired on PBS and it covers the graffiti scene at around the time that hip hop was emerging from the city.
The documentary followed a book of the same name by Norman Mailer, Watching My Name Go By, which contains page upon page of great photos of graffiti from the time. It can be a very difficult book to lay your hands on (probably need to watch listings until one becomes available).