Chris Kirby’s review published on Letterboxd :
A feature length documentary included on Synapse's BD release of Tenebrae.
The documentary is really just a long series of interviews that have the participants progressing through the history of Giallo. It's definitely more Bonus Feature material than an actual standalone film. There's a ton of great insight and information and it's just enjoyable listening to all of these individuals speak. The participants include Argento, Umberto Lenzi, Ruggero Deodato, and Luigi Cozzi. It's pretty great.
Seeing as it is a bonus feature for Argento's Tenebrae it is no surprise that the discussion is very heavily focused on Argento's work. However, it is called The Rise and Fall of the Giallo; so it would have been nice if that was what they talked about...and not just Argento with a few asides.
Overall it's very informative and entertaining but is extremely atypical of DVD bonus feature documentaries that are just edited interviews. Nothing special but not unworthy of your time. Though, I really hope this was actually filmed at least a year and a half ago. At the end Argento is asked if he has any plans for a new film and he replies "No. Nothing in the works." So hopefully this is an older interview (delayed in release obviously by the delay in the release of the Tenebrae BD) because else wise that would mean he either forgot about The Sandman or he took my Indiegogo money and ran. Which would be incredibly upsetting.