What did I learn from watching “Ennio” (2021), director Giuseppe Tornatore’s epic love letter to his regular musical collaborator, the late Ennio Morricone? A lot, actually. At some points, perhaps even too much.

I always knew the composer was a little exasperated by his continued association in many people’s minds with “spaghetti westerns.” Of course, he’d written music for dozens of them, but they were a mere fraction of his overall output of some 500 film and television scores. What I didn’t know is that, according to him, both he and Sergio Leone disliked the music for his revolutionary score to “A Fistful of Dollars.” You know, the one that changed movie music forever, certainly that for westerns and especially Italian westerns. The artists seemed to like it well enough in the moment, but by the time they got around to working on the sequels, they were over it. Good thing Ennio pushed through to compose the music for “The Good, the Bad and the Ugly,” which is quite simply one of the most recognizable film scores ever written. Right up there with “Psycho” and “Jaws” in terms of instant identification by your average person on the street.

Morricone and Tornatore’s working relationship began with “Cinema Paradiso,” which the composer agreed to score at a time when he was one of the most famous in the world (with 350 of his scores already written) and the director was only just starting out. Decades later, when Morricone talked retirement, he specifically cited Tornatore’s films as being among the few projects that could ever entice him back. Sort of like John Williams with Steven Spielberg. But to my knowledge, Williams never was so divided about his occupation or so vocal about his reservations.

If you’re a filmmaker and you hire Ennio Morricone, in the names of all saints in Heaven, do not tell him what to do! Unquestionably, he has his own ideas. Send him a script and let him watch the movie, and then get out of the way. Otherwise, like Oliver Stone, you’ll get a taste of his testiness and understand in no uncertain terms that you are an idiot.

Not that Morricone is at any point discourteous to anyone. He just has strong convictions about what a specific film requires. He has his vision, and he is unwavering in the drive to realize his musical ideas.

We also learn how sensitive he is. He talks with palpable ambivalence, describing his longtime struggle to come to terms with his chosen profession. He so desperately craved the approval and acceptance of his father, his teacher, and his colleagues in the world of classical music. Even all these years later, his emotional and psychological struggles are evident.

According to Roland Joffé, when he first showed him “The Mission,” Morricone dissolved into tears, he found it to be so moving. He asked Joffé what he could possibly want from him. The movie required no music, he said; it was perfect as it was. Then he went home, and later the motif for “Gabriel’s Oboe” popped into his head. The score went on to become one of Morricone’s most recognized and revered. He was robbed of the Academy Award for Best Original Score that year when the Oscar went to “Round Midnight,” the soundtrack of which consisted mostly of preexisting classics by established jazz artists. It could be argued that it didn’t even belong in the same category. But Herbie Hancock, who provided what little original music there was in the film, accepted the award, and he was and remains an outspoken Morricone admirer.

Morricone would be nominated for – and lose – the Oscar five times before the Academy finally gave him an honorary award in 2007. Then he went on to win a competitive Oscar in 2016, at the age of 88, for his music for Quentin Tarantino’s “The Hateful Eight.” That he would remain so long underappreciated by the Academy is unfathomable. But he did live through an era when the competition was much stronger than it is now (“Round Midnight” aside).

The most revelatory parts of the documentary come in the first half hour, when we learn about Morricone’s early years, following in his father’s footsteps as a working musician, as opposed to an artist, earning the family bread using the cheapest secondhand trumpet his dad could find, playing gigs in orchestras and dance bands. Then his pursuit of excellence as a classical musician, and a composer, studying with Goffredo Petrassi. And after that, wandering further into avant-garde experimentation, first in Darmstadt, the epicenter of plinks, planks, and plunks, and then with the group he himself formed, Il Gruppo di Improvvisazione Nuova Consonanza (G.I.N.C.) .

The documentary does a great job of showing how these influences carried over into his music as an arranger for pop singers, and it’s hilarious, once it’s pointed out, to grasp just how crazy – and inspired – his choices were, in terms of including extramusical effects in these hit songs. So the spaghetti western sound of whip cracks, whistles, and nonsense choruses did not develop in a vacuum. At a point, Morricone brings some pretty hardcore avant-garde experimentation to bear on his film scores, with the G.I.N.C. improvising in some 40 films, until the suits finally pull him aside and say, Hey, Ennio, enough already!

There’s lots of great, rarely-seen footage of young Morricone in his nerd glasses, looking, as someone describes, all the world like a Peanuts character. But there’s so much, it seems like an awfully long time passes before we finally get to the spaghetti westerns that made him so famous. At that point, of course, even the most casual Morricone fan will sit up and take notice.

Then there will likely be a dip in interest, except perhaps for diehards and fans of international cinema, as there are discussions of films many Americans will be unfamiliar with, save perhaps something like “The Battle of Algiers,” which was regarded as significant enough that it made it to U.S. theaters. But many of the directors Morricone worked with were major players in world cinema, and a number of these are included among the talking heads.

One of the weaknesses of the documentary is its assumption that its audience really knows its stuff, to the extent that many of those who offer their onscreen commentary are not really identified beyond their names. So you have to fill in the blanks a little bit, in terms of who was a director or a work associate or a fan from another genre of music you might not be so familiar with. Again, if you’re really into Morricone and world cinema in general, you will likely recognize just about everyone, but I was relieved when there was finally some footage that explained who Alessandro Alessandroni (Morricone’s whistler and guitarist) and Edda dell’Orso (who provided the haunting vocalises for classic scores like “Once Upon a Time in the West”) are.

Also, are there any subtitles in this movie? For a documentary about a figure of international appeal, with so many of the onscreen participants speaking different languages, you would assume that there would be English subtitles. That well may be the case, but if so, for some reason they were not showing up on my print (I streamed it on Prime), so I wound up having to resort to closed captioning.

What comes across loud and clear, in whatever language, is that Tornatore loves Morricone. And why wouldn’t he? He enjoyed the privilege of being favored by one of the greatest geniuses of his art form. However, it is possible he loves him just a little too much. He is so close to his subject, he can’t seem to look away. While unquestionably a feast for Morricone admirers, the film, I’m sure, could be tightened by a good half hour. The running time is 150 minutes, nearly as long as “The Good, the Bad and the Ugly” itself (which I rewatched the next night). There’s a lot of repetition in the commentary of the talking heads, and I wonder if some of them even had to be there at all.

Perhaps partly it was a question of securing funding, or at any rate audience identification. If you can get Bruce Springsteen to come on and say he loves Morricone, great, but he really offers nothing substantial, certainly no insights. And then once you’ve got him to participate, you’ve got to have him in there enough to make it worthwhile. There are several such witnesses included. I found it much more interesting when the guy from Metallica shows up to offer a few remarks and we see him play “The Ecstasy of Gold” in concert. That was awesome. Really, between that and Morricone’s own concert footage, anyone will walk away understanding that the composer himself enjoyed the status of a rock star. At the end of his life, he toured everywhere, selling out arena after arena all over the world.

Tornatore began filming the documentary while Morricone was still alive, so we’re very lucky to have so many clips of the composer recollecting everything, including his work on so many of his major scores. For a guy who worked so much (there were years when he composed more than 20 scores), he seems to remember every musical phrase. Most shocking admission by the composer: that he hates melody! But I think we can take that with a grain of salt. These segments are gold.

And by the time we get to “Days of Heaven,” anyone who lived through the era realizes what a golden age it was. In the late ‘70s and 1980s, Morricone quietly revivified even American movies.

The verdict: “Ennio” is definitely worth seeing, most of all for Morricone fans; then for those that love the movies in general; and then for anyone who is curious about the fascinating path an artist’s career can take, and how expertly Morricone navigated the then-divergent fields of classical, avant-garde, popular, and film music. He really was forward-looking in his embrace and mastery of different forms, anticipating the now common practice of hurdling barriers that used to stand impenetrable between genres.

The trailer is superb. Whoever edited it should have put together the movie.

“Ennio,” a solid three out of four stars. Indispensable for lovers of Morricone and, more broadly, film music, and an interesting watch, if a long one, for everyone else.