This TV documentary was broadcast on September 16, 1977. Just 4 months after Star Wars: A New Hope hit theatres. I remember being bummed that I missed it (because I didn’t own a TV in ’77). Hosted by R2D2 and C3PO, it gives a glimpse of the process that would spawn a whole new genre of film and create several new companies.
Some of it was shot while the movie was in production but much of it was recorded in that 4 month period after release, when it was clear that Star Wars was a phenomenal cultural-changing success.
It’s pretty obvious, despite his later claims, that George Lucas had no intention of filming the subsequent episodes until after the success of the original was well established.