"La corta notte delle bambole di vetro" can be considered as the first political giallo.
Most reviews stress the fact that it's a vibrant allegory about repression in communist dictatorships. It is probably true considering the very obvious (almost "in-your-face") symbols Aldo Lado is using:
it is set in Prague (just after the "Prague Spring" in 1968) and tells the story of how Gregory Moore, an American journalist, and his girlfriend called Mira Svoboda - which means "freedom" in Russian -, are becoming preys of a secret society.
But in the Anchor Bay DVD, there's an interview of Lado where he says the idea actually came out of the Italian news: a judge who was getting close to unveil political scandals was suddenly transferred to some remote town in the south of Italy in order not to cause any trouble.
When you become a threat to the power in place, you are literally buried alive.
This idea just reveals the extreme tensions existing in Italian society and politics in the early 70s.
More about "Short night of the glass dolls" from this blog here, and a good article about it from braineater.com there.