Over 90% of dialog in film was improvised.
The original was not pre-written; it was created on the spot, i.e. unscripted.
The scripted scene, "Shop of Shattered Dreams", comes from a stage improv from several years earlier.
Filming on stage was based on a few notes, and some bullet points. The original was an improv performance from a few years ago.
All location dialog and voiceover was extemporaneous as the mood of the place and time inspired.