In My Octopus Teacher, the Academy Award–winning 2020 Netflix documentary, filmmaker Craig Foster chronicles his yearlong relationship with an octopus living in a South African kelp forest. The creature is passing strange when he first spots it, hiding itself in a cloak of shells to lure its prey into a false sense of safety. By the end of the film, however, when the octopus inevitably dies after laying her eggs, his loss feels wrenching, like the demise of the spider made lovable in the course of Charlotte’s Web. This notion is right there in the title: What the animal taught the man was how to “feel” again. “A lot of people say an octopus is like an alien,” Foster’s voice-over narrator remarks. “But the strange thing is, as you get closer to them, you realize that we’re very similar in a lot of ways.”
We’re not, though. As Ha Nguyen, a marine biologist in Ray Nayler’s scintillating debut novel, The Mountain in the Sea, explains, octopuses are solitary animals while humans are highly social, and octopus life spans are short: an average of three years, with many species living only a year. Ha—who has written a speculative book on the possibility of octopus consciousness—also points out that once octopus eggs hatch, “the young of most species float to the surface and drift in the plankton before settling to the bottom at another location. That kills any connection to place or kin.” To produce consciousness as we understand it, she declares, “you would need to have a creature that is long-lived, that is social, that raises its young, and can pass information from one generation to the next. An octopus that has developed a complex, symbolic system of communication.” As far as we know, Ha says, such an octopus doesn’t exist.
Nevertheless, Ha has agreed to study a rumored octopus colony that might possibly fit that bill at an environmental reserve on the remote Vietnamese archipelago of Can Dao. The Mountain and the Sea, a fusion of techno-thriller and novel of ideas, reveals what she finds there while also offering intriguing glimpses of the larger, near-future world beyond Can Dao. One of the archipelago’s islands in particular has long been the subject of legends concerning a sea monster. Villagers have seen strange shapes on the beach or discovered the bodies of people killed in mysterious attacks. When the novel opens, however, there are no villagers left to whisper about the place because an international corporation called DIANIMA has bought the whole reserve and ejected its occupants.
Put up by DIANIMA in an abandoned beachfront resort, Ha considers the octopuses and their society, while mostly starved of human society herself. Her only companions are a surly security guard named Altantsetseg—a Mongolian woman who’s a veteran of a punishing Asian war—and Evrim, the world’s one and only android. Created by the scientist who founded DIANIMA—a figure who hovers at the periphery of the novel as a string-pulling mastermind—the ungendered Evrim provoked so much popular outrage upon their debut that they have been relegated to this remote outpost on an assignment designed to keep them out of the public eye. Nayler depicts the android as elegant and mournful, a quoter of Shakespeare (The Tempest, of course) who can’t eat the macaroon the newly arrived Ha offers as a gift but wants to hold onto it anyway because “I have never been given anything quite like it.”
Ha isn’t sure, at first, if the octopus colony represents a new strain of superintelligent cephalopods, but she soon learns that it is remarkable simply for bringing so many of the creatures together. (Two real-life exceptions to octopus solitude, Octopolis and Octlantis, are settlements characterized by constant conflict and occasional cannibalism.) As the Can Dao team begins its investigation, however, it soon sees signs of something more than the usual Hobbesian war of mollusk against mollusk. Is that aging octopus actually being protected by its fellows? And what is the meaning of an extraordinary interaction in which an adult octopus uses its ability to change the color of its body to flash a series of repeating patterns at a younger animal?
Orbiting this central story are two suspenseful subplots whose connection to Ha’s storyline are only slowly revealed. In one, Rustem, a particularly intuitive—and therefore uniquely gifted—Russian hacker accepts a job from a woman wearing a digital mask that conceals her face. She acts on behalf of a shadowy organization that wants him to find a back door into a formidable neural network. In the other subplot, a young Japanese man applying for a position at the regional headquarters of DIANIMA in the Ho Chi Minh Autonomous Trade Zone is shanghaied from a brothel and wakes up enslaved on a massive fishing vessel run by artificial intelligence and patrolled by heavily armed mercenaries. Does the kidnapped workers’ desperate plan for a mutiny stand a chance?
The Mountain in the Sea is a novel that wears its themes on its sleeve, but the ideas it tangles with—ideas that may feel especially pertinent at the moment but are actually as old as humanity itself— are so intriguing that this hardly matters. Alone on the island, Ha, Altantsetseg, and Evrim struggle to come up with definitions of consciousness, selfhood, and culture that can fit both human beings and octopuses. And Evrim, too, wonders about their place at this table; the great question of their life is whether they are truly conscious or merely a simulacrum of a human mind.
In Evrim, Ha recognizes a being made of human ingredients—the android has been installed with the “complete neural connectome” of their brilliant creator—who also becomes less and less human over time because of their perfect recall. “That’s what we are, we humans,” Ha reasons, “creatures that can forget.” While we typically see forgetting as a loss, the fact that “nothing can reside in our minds forever, etched into us,” means we can “replace our old selves with new ones.” Nayler no sooner raises this striking point—isn’t the ability of living creatures to remake themselves somehow central to the condition of begin alive?—than he does a counterpoint. Eiko, the enslaved man on the fishing boat, believes that the only way to hold onto his humanity is to carefully maintain an elaborate memory palace to prevent him from forgetting anything about his experience on the ship. Eiko is convinced that it was his inattention to the world and people around him that led him into his predicament.
To be conscious, as Ha figures it, the octopuses need language—a tool for remembering, and for passing on what they remember to others. To produce language, they must have a community to share it with. But The Mountain and the Sea slyly observes that our species isn’t as proficient with such prerequisites of consciousness as we would like to believe. Altantsetseg deliberately uses a janky translating device that produces a brusque, stilted version of her own speech in order to keep people at arm’s length. “I don’t always want to have a conversation,” she explains to Ha. “In fact, I almost never want to have a conversation.” Ha, an orphan wounded by an intense, formative experience of unrequited love, feels that she has lived her life at a distance, “as if somewhere behind glass” there was “another Ha, always untouched, observing and never being observed.” It’s not just the Can Dao team, either. One of the shadowy DIANIMA founder’s most popular inventions is an artificial companion known as a point-five. What most people want, as one character puts it, is not a relationship with another fully formed person: “They want to be the complete one, the person who controls the relationship—and they want the other person to be half a person. You know, someone who gets them, but who doesn’t have their own demands.”
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Why do creatures made so uncomfortable by genuine interaction with one another desperately want to connect with yet another conscious species? And why would such a species, if it had any sense, engage in such contact? The primary message the octopuses wish to get across to humanity is “go away!” But by using cloaked drones (Altantsetseg is the wizardly operator of an entire fleet of them), the Can Dao team learns enough about the colony to begin to worry about what will happen to it once word gets out. And what are DIANIMA and its creator’s intentions for Can Dao, anyway? To judge from their past actions, nothing good.
The Mountain in the Sea has some talky patches, especially the parts where Ha and Evrim hash out the meaning of the team’s work. But Rustem’s and Eiko’s parallel storylines inject action into the novel while sustaining Nayler’s point that humanity needs to get its own house in order before it starts looking for company in the universe. What does it signify to quibble about Evrim’s status as human when the fishing ship treats people like nothing more than machines? At what point does Rustem’s ability to imagine himself into artificial minds lead to an empathy that will oblige him not to interfere with them? Nayler has a gift for summoning up a sense of place, whether it’s the rainy streets of the Ho Chi Minh Autonomous Trade Zone at night, where “electric motorbikes swept past like luminescent fish,” or the deserted resort commandeered by the Can Dao team, where “torn curtains bled through the broken windows on the upper floors” and “ribbons of damp and mold streaked the facade.” And however weighted the characters’ relationships are with such big themes, they still play out with a pleasing dramatic flair: You can tell Altantsetseg has finally warmed to her fellow team members when she switches to a better translating device.
Nayler works with marine sanctuaries at the National Oceanic and Atmospheric Administration. Given this day job, it’s unsurprising that the novel does briefly tip into didacticism about how people ought to care more about one another and the environment. Still, the imaginative stretches the novel calls for—the consideration of what shapes minds might take in bodies radically different from ours—make up for the occasional finger wagging. His octopuses are so much more than teacherly dispensers of life lessons, and fortunately, this wondrous novel is, too.
