I first read this a few years back and just finished reading it for the third time.
This is one of my favorite (top 10) modern (1978) classics of Italian literature.
I love the time period—a simpler, more innocent time. I love the academic setting. I love the sly, subtle (and sometimes not-so-subtle!) irony. I love the description. I love the characters.
Mostly, I love the skill and elegance of the language Pontiggia uses (I read the Italian original).
The main character is a university professor (we never know his name) whose academic work is called into question by a sly, passive-aggressive, anonymous letter to the editor of some literary/academic journal. The letter basically calls into question the professor's conclusion about the etymology of a word, so it's light years away from the sort of attack we see in today's social media. Like I said earlier, a simpler, more innocent time.
The professor becomes hilariously obsessed with discovering who wrote it (analyzing the words the writer used and trying to remember which of his frenemy colleagues uses the same words). He meets many of those frenemies, ostensibly to seek out advice, but really to "feel them out" and try to figure out who "hates" him so much. They all basically point the finger at each other.
Complicating matters, the professor has a young (student-age) mistress who's trying to win a poetry competition, and his wife is also seeing a man on the side, a man who used to be the professor's student.
The "invisible player" is a reference to chess, which appears through the narrative several times, in different ways. In one scene, the professor wants to buy a certain chessboard and makes a bit of nuisance of himself with the shopkeeper.
The true strength of the narrative lies in the atmosphere and the description and the humor and the characters which each have a distinct, real personality and quirks. Every paragraph is a joy to read, even when the story becomes less interesting.
Yes, somewhere about two-thirds of the way in, I think the book runs slightly off the rails, and falls just short of true perfection. I think the narrative sputters and loses momentum with the many scenes that, although interesting and well-written, don't really advance the plot, and perhaps don't even involve the main plot in any way. It almost feels like the main story is just a loose frame to help unite a number of interesting anecdotes and quirky characters together.
To avoid any spoilers, I won't go into detail about the ending, but I'll say that it was less than satisfactory to me.
Still, a great book, very enjoyable, and on the shorter side, so a quick read. Perfect to take to the beach or the pool.
Highly recommended!