The Scottish author Iain Banks famously led a double life in publishing. Some of his books—the ones published under the name Iain Banks—were sold to readers as “literature,” and shelved as such in bookstores. The rest—the ones that applied his talent for crafting boldly unlikeable characters and tossing them into enormously complex plots laden with the tropes and trappings of science fiction—were published under the name “Iain M. Banks,” that middle initial serving as a beacon to genre readers across the world, telling them: this one. This is the Banks you’re looking for.

The Algebraist is peak Iain M. Banks. It’s also the only book he ever wrote to be nominated for the Hugo Award, a fact that seems almost unbelievable in retrospect.

The late, great SF pioneer, who died on this day in 2013, spent most of his life experimenting with space opera, reinventing and perfecting the form across works like the expansive Culture series and the space opera noir Against a Dark Background. In countless interviews, he talked about how the best science fiction writing demanded a huge canvas—a near-infinite universe of shiny spaceships and bizarre aliens, filled with danger and adventure in equal measure. To be sure, The Algebraist delivers all of this in spades, and displays Banks’ off-kilter sense of humor, penchant for dropping his characters into unusual and dangerous situations, and his constant balancing act between anti-fascist leanings and appreciation for fictional weaponry.

But rather than the cynicism, absurdity, and sometimes outright bleak tone of his earlier works, The Algebraist retains a degree of hope with regard to its universe, adding light and heroism to the dastardly villains, coloring them in shades of grey.

Fassin Taak is a “slow seer,” employed by the theocracy of Mercatoria to delve through the research archives of the millennia-old Dwellers, who live inside gas giants. Most of what the Dwellers give up is academic— a bit of poetry here, reams of history there—but occasionally, something useful pops up. On one of his delves, Fassin is given a clue to a secret network of interstellar portals, unwittingly catching the attention of both anarchic space pirates and the psychotic forces of the Starveling Cult, who cut off Taak’s home system of Ulubis from the galactic wormhole network, then send out their entire fleet at sub-light speeds to steamroll them into oblivion in pursuit of this galaxy-changing intel.

With the fleet at least a year out, Mercatoria sends their own ships to intercept, hoping to arrive before the Cult forces. In the midst of this terror, Taak is drafted against his will by Mercatoria to find the portal network’s key and save his system—if he can decipher the clues in time.

The Algebraist displays a major tonal shift for Banks. While his other space operas tend to focus on deconstructing the “lone hero saves everyone” trope, this one instead celebrates a certain sense of idealism through an individual. Fassin Taak might be an intellectual, but unlike his fellow Seers, he’s willing to risk life and limb to meet and talk directly to the Dwellers on their level (their level being hundreds of miles deep into the inhospitable atmosphere of a gas giant, remember). He steadfastly refuses to give in to the government on several occasions, until it’s made clear that Mercatoria will start targeting his family, his friends, and even entire branches of their own society if he doesn’t cooperate. He’s also more willing to try to understand a given situation instead of just reacting to it, and to his credit, Banks rewards this behavior. The author even extends a certain idealism toward the government of Ulubis, showing them as flawed, but not completely irredeemable—despite their rigid hierarchy.

Lest you think this a departure into completely conventional space opera, rest assured: this is still very much an Iain M. Banks novel. The mission statement seems to be “everything you already loved, but bigger and brighter.” There are still plenty of splashy Banksian flourishes to savor: genetic engineering, odd bureaucratic and militaristic quirks, a villain who executes a would-be assassin by forcing him to grow his canine teeth through his skull. His skill for creating truly strange aliens—including a spider-like race that talks “like a child with a mouthful of ball bearings” and gigantic bat/praying mantis hybrids—has rarely served him better.

Yet, in a refreshing move for space opera, The Algebraist positions humans as the most prominent race in the galactic milieu; thanks to a frowned-upon practice called “prepping”—in which advanced races “borrow” embryonic specimens from “pre-civilized” species to seed across the galaxy, with the intent that a planet’s upstart native population will be in the minority among their kind once they manage to achieve interstellar spaceflight—we’ve been populating the stars like rabbits for abut 8,000 years by the time the book begins. Banks’ sardonic sense of humor also comes into play—he’s often credited for his big ideas, but rarely gets his due for just how offhandedly funny his books are. Characters snark back and forth at one another even while being tortured; elsewhere, a fleet’s flagship is named after the rifle purported to have killed JFK, and the Dwellers stage drunken battles to keep themselves amused during their billion-year lifespans. With the more idealistic focus to guide him, Banks lets loose, sketching wild flights through gas giants and titanic battle sequences between millions of starships in a way his other novels approach, but never fully embrace.

This book is a true achievement in science fiction in a bibliography full of them, turning a master author at the pinnacle of his powers loose in a massive sandbox of his own design, but retaining enough charm and accessibility to engage readers rather than lose them in excess and indulgence. It brings together all the worldbuilding skill Banks perfected throughout his career, and presents it with a sense of wonder that is absolutely infectious.

Is it the best book Iain M. Banks ever wrote? That’s a question with as many answers as there are readers. But it is, perhaps, the most Iain M. Banksian.

What’s your favorite Iain Banks novel, with the M. or without?