Allow me to confess a shameful secret: I am constantly losing track of Game of Thrones characters. This debility afflicts me particularly during the long winters between seasons. When someone who vanished from the story years ago suddenly reappears, I don’t shout, in the manner of the true Throner, “There he is!” I’m more likely to frown and say “Who’s that again?” and reach for my iPad.

Game of Thrones, which returned for its seventh season on the weekend on HBO, is the most complex and convoluted television show in the history of the medium. That complexity is half the fun.

And fun it is. Last season, the show averaged 7.7 million live viewers per episode — 10.6 million when we include those who viewed it on other media within seven days. Total viewers per episode averaged in excess of 23 million. The season finale drew a 4.4 rating in the 18-49 demographic that advertisers love, a figure that beat every scripted show on broadcast or cable except Empire and The Walking Dead.

Game of Thrones is special. No other scripted show generates an online community of a richness and depth usually reserved for big-screen franchises with “Star” in the title. Apart from the Super Bowl, nothing else on television sparks parties where fans expert and casual mingle as they await every twist and turn.

The show has been called, with reason, the last bit of television monoculture. People watch it, and discuss it, and argue about it; and in a certain age and cultural cohort, those who would rather skip it are left out of the conversation. But millions of us outside the cohort also tune in.

Why do we watch, captivated? Part of the reason is that everyone else watches. Potential viewers, younger ones particularly, do not want to be left out.

But there are other reasons. Many fans cite the complexity of the world-building, both in the books and in the television show. And the world-building is indeed a delight, even when one spots the holes. (How can the society exist with only one bank? Why don’t the various would-be conquerors loot it?) Other viewers point to the constantly shifting alliances ... and betrayals. The sets are remarkable. (At $10 million per episode, they had better be.) There are wonderful villains (Tywin Lannister) and wonderful anti-heroes (Tyrion Lannister).

And White Walkers. And dragons.

There are the constant surprises, particularly the willingness to kill off leading characters, not just minor ones, often without warning. If you miss an episode you may miss a major death.

This technique, pioneered by The Sopranos, has become a staple of so-called prestige television drama — Breaking Bad; Sons of Anarchy. But Game of Thrones has raised the killing of characters to an art form, setting up sequences in which fan favourites are cut bloodily and suddenly from the story.

Still, I bet I’m not the only fan who cannot keep all the storylines and characters straight. I am always confusing the Maesters. I have only the vaguest memories of Dontos Hollard and the High Septon. If I want to know what “valar morghulis” means, I have to look it up. I am aware that Gendry is still rowing but I have trouble remembering that the place he escaped from is called Dragonstone. (I also used to forget which Clegane was which, but I finally have that one straight.)

And none of this matters — not to me, and not to all of the other millions of viewers who don’t have the map of Westeros committed to memory and can’t quite recall all the clues in Bran’s visions. For some of us, not being able to keep track is part of the fun. The Sopranos never called upon viewers to hold in their minds the details of more than perhaps a dozen characters in any given season — except, arguably, the last. The number who really mattered at any moment of Breaking Bad — or in the first season of The Handmaid’s Tale, say — was even smaller.

But in Game of Thrones, the viewer never knows which long-vanished cast member will suddenly show up to save the day or ruin it. (Lancel Lannister, for instance.) Over six seasons, the total number of named Game of Thrones characters is — wait for it — 553.

How many of these should be considered leading characters? Estimates range from about 50 to 150. It is preposterous to think that many of those who attended the weekend’s kick-off parties can tell them all apart. On the contrary. Most of the record number of viewers expected for the season opener are surely more like me. The impossibility of keeping track of everything and everyone is a feature, not a bug. I enjoy the way that I am constantly surprised.

The plot, too, is of such stupefying complexity that hardly anyone can reasonably claim to be following it all. We know that everyone is battling over the Iron Throne, and that anyone who gains it probably has but little time to live. The rest is betrayal and blood, blood and betrayal, and, every now and then, character growth. (Brienne of Tarth.)

But in truth, there is no real need to keep track. The twists and turns, the swords and the legends, the angry diatribes and snappy dialogue all work even if you do not remember who’s who. If I should happen to tune in halfway through some long-forgotten episode from Season Two, I would be engrossed at once.

There are blind spots. Too much rape, for one thing. Too much talky exposition about details from the books. Too much effort put into trying to get us to root for a character who in Season One threw a child out the window in an effort to cover up his own incest.

Yet, that said, Game of Thrones remains the most remarkable television phenomenon of our time. I’m excited that Season Seven has begun, and sorry that Season Eight will be the last. I will never remember all the characters, but I will never forget the experience. Television’s golden age will surely outlast Game of Thrones. But I don’t think we will ever see a show such as this again.

•Stephen L. Carter is a Bloomberg View columnist. He is a professor of law at Yale University and was a clerk to US Supreme Court Justice Thurgood Marshall. His novels include The Emperor of Ocean Park and Back Channel, and his non-fiction includes Civility and Integrity