To the remote planet Spatterjay come three travelers with very different missions. Janer is directed there by the hornet Hive-mind; Erlin comes to find the sea captain who can teach her to live; and Keech—dead for seven hundred years—has unfinished business with a notorious criminal.

Spatterjay is a watery world where the human population inhabits the safety of the Dome and only the quasi-immortal hoopers are safe outside amidst a fearful range of voracious life-forms. Somewhere out there is Spatterjay Hoop himself, and monitor Keech cannot rest until he can bring this legendary renegade to justice for atrocious crimes committed centuries ago during the Prador Wars.

Keech does not realize that Hoop’s body is running free on an island wilderness, while his living head is confined in a box on an Old Captain’s ships. Nor does he know that the most brutal Prador of all is about to pay a visit, intent on wiping out all evidence of his wartime atrocities. Which means major hell is about to erupt in this chaotic waterscape.

“Asher will definitely appeal to connoisseurs of sophisticated adventure-oriented SF.”
—Publishers Weekly

The Sharers of Shora are a nation of women on a distant moon in the far future who are pacifists, highly advanced in biological sciences, and who reproduce by parthenogenesis. There are no males. Conflicts erupt when a neighboring civilization decides to develop their ocean world, and send in an army.

“An intriguing ocean world…[The] schematic political framework is enlivened by the full-blooded characters who negotiate between the two cultures.”
—Publishers Weekly

On an oil platform in the middle of the North Atlantic, a terrifying series of illnesses is spreading through the crew. When naval doctor Peter Crane is flown in, he finds his real destination is not the platform itself but Deep Storm: a top secret aquatic science facility, two miles below on the ocean floor. And as Crane soon learns, the covert operation he finds there is concealing something far more sinister than a medical mystery—and much more deadly.

“Clever… A sci-fi mystery thriller.”
—San Jose Mercury News

After narrowly escaping death in a forest fire, Angie Dinsman finds herself under the control of the World Life Company. They promptly equip her with webbed hands and gills, creating a half-fish, half-woman. Her mission is to uncover secret research files on the waterworld of Lesaat. But first she has to undergo the terrifying process of learning to breathe underwater. After mastering the basics of survival, she faces an insurmountable challenge: finding the information that could end starvation on Earth while sabotaging the Company’s evil plans.

Author Carol Severance comes by her knowledge of Polynesian culture and mythology honestly: she served with the Peace Corps from 1966-1968 and later assisted in anthropological fieldwork in the remote coral atolls of Truk, Micronesia. Eventually, she moved to the Big Island of Hawaii and worked as a journalist.

Reefsong isn’t well known, but it definitely has a cult following—all of its reviews have five stars. A typical example:

“A nice blend of fantasy (mostly) with a little sci-fi thrown in–a fast-moving, thought-provoking story in a gorgeous other-worldly Pacific-Islandesque setting with a strong, smart heroine at its center.”

This is probably the least science-fictiony book in the list, so depending on your mood, you might be ready for a tropical planet story.

The Kraken Wakes is about an alien invasion—from the sea.

John Wyndham (pseud. for John Beynon Harris) is best known for his classic Day of the Triffids. Like that book, this one posits an intelligent species with needs and aims unimaginably different from our own, and describes the escalating phases of what appears to be an invasion of Earth by never-seen aliens.

Reviews are generally excellent, but some people on Goodreads were put off by the decidedly non-feminist treatment of female characters.

In total, The Kraken Wakes is a good read that shows its age.

The artifact is found seven miles below the surface of the sea and beneath 40 more feet of sand. The Navy’s efforts to raise a wrecked submarine uncover it, and set in motion a scientific race to retrieve it, to discover just what it is and where it came from.

Denser than any substance known to man, it has broken every drill bit they’ve tried on it and will not budge an inch. It resists every effort to breach it—or communicate with it. So the government turns to marine biologist Russell Sutton for help.

Meanwhile, unknown to any of them, two creatures have wandered the earth for generations. The aliens have no knowledge of each other, but possess a residual memory of the artifact—and an affinity for deep water. One, which calls itself the changeling, has survived by adaptation, by taking on many different forms: man, woman, snake, shark. The other, which calls itself the chameleon, has survived solely by destroying anything or anyone that threatens it.

Now, finally brought up from the bottom of the sea, the artifact calls to them both… to come home. For all these generations there have been two invincible creatures on Earth. But the chameleon has decided there’s only room for one.

“An extremely intelligent thriller.”
—Washington Post

Whales begin sinking ships. Toxic, eyeless crabs poison Long Island’s water supply. The North Sea shelf collapses, killing thousands in Europe. Around the world, countries are beginning to feel the effects of the ocean’s revenge as the seas and their inhabitants begin a violent revolution against mankind.

Some of science in The Swarm is undoubtedly due to Thomas Orthmann, a German marine biologist and journalist, who claims that dozens of passages in The Swarm have been lifted word for word from his writings. Currently, he is demanding compensation from Schätzing, who refuses to pay. He has, however, agreed to acknowledge Dr. Orthmann in the next edition of The Swarm.

Most reviewers agree that despite its flaws of thin characterization, pages upon pages of scientific explanations, and strong anti-U.S. sentiment, The Swarm is a thrilling read.

Brin’s tales are set in a future universe in which no species can reach sentience without being “uplifted” by a patron race. But the greatest mystery of all remains unsolved: who uplifted humankind?

The Terran exploration vessel Streaker has crashed in the uncharted water world of Kithrup, bearing one of the most important discoveries in galactic history. Below, a handful of her human and dolphin crew battles an armed rebellion and the whole hostile planet to safeguard her secret—the fate of the Progenitors, the fabled First Race who seeded wisdom throughout the stars.

Winner of both the Hugo and Nebula awards, Startide Rising is the second book in the Uplift series (there’s a total of six), but popular opinion has it that the first book, Sundiver, can be safely skipped.

This book is essentially Moby Dick in the future.

When seventeen-year-old Ishmael wakes up from stasis aboard the Pequod, he is amazed by how different this planet is from the dirty, dying, Shroud-covered Earth he left behind. But Ishmael isn’t on Cretacea to marvel at the fresh air, sunshine, and endless blue ocean. He’s here to work, risking his life to hunt down great ocean-dwelling beasts to harvest and send back to the resource-depleted Earth. Even though easy prey abounds, time and again the chase boat crews are ordered to ignore it in order to pursue the elusive Great Terrafin. It’s rumored that the ship’s captain, Ahab, lost his leg to the beast years ago, and that he’s now consumed by revenge. But there may be more to Captain Ahab’s obsession. Dark secrets and dangerous exploits swirl around the pursuit of the beast, and Ishmael must do his best to survive—if he can.

“[A]n old-fashioned maritime adventure, filled with details of the sea life: close quarters, harpoon hunts, pirate attacks, storms, and shipwrecks. Strasser… adds dystopian corporations, time travel, a secret legacy.”
—Booklist

Crichton says he started writing the novel in 1967 as a companion piece to The Andromeda Strain. He began with American scientists discovering a spaceship underwater that had been there for 300 years but with stenciled markings in English. However, after that beginning, Crichton realized, “I didn’t know where to go with it,” and put off completing the book for twenty years until he decided what an alien should be.

As with most Crichton novels, Sphere is gripping and thoughtful until it unravels into a disappointing ending.

This book leans more toward steampunk fantasy than strict science fiction.

Aboard a vast seafaring vessel, a band of prisoners and slaves, their bodies remade into grotesque biological oddities, is being transported to the fledgling colony of New Crobuzon. But the journey is not theirs alone. They are joined by a handful of travelers, each with a reason for fleeing the city. Among them is Bellis Coldwine, a renowned linguist whose services as an interpreter grant her passage—and escape from horrific punishment. For she is linked to Isaac Dan der Grimnebulin, the brilliant renegade scientist who has unwittingly unleashed a nightmare upon New Crobuzon.

For Bellis, the plan is clear: live among the new frontiersmen of the colony until it is safe to return home. But when the ship is besieged by pirates on the Swollen Ocean, the senior officers are summarily executed. The surviving passengers are brought to Armada, a city constructed from the hulls of pirated ships, a floating, landless mass ruled by the bizarre duality called the Lovers. On Armada, everyone is given work, and even Remades live as equals to humans, Cactae, and Cray. Yet no one may ever leave.

Lonely and embittered in her captivity, Bellis knows that to show dissent is a death sentence. Instead, she must furtively seek information about Armada’s agenda. The answer lies in the dark, amorphous shapes that float undetected miles below the waters—terrifying entities with a singular, chilling mission….

“[S]tate-of-the-art dark fantasy.”
—Publishers Weekly

Highly acclaimed when released and even now, Twenty Thousand Leagues Under the Sea is regarded as one of the premiere adventure novels in literature and one of Verne’s greatest works, along with Around the World in Eighty Days and Journey to the Center of the Earth. Verne himself has been the second most-translated author in the world since 1979, sandwiched between the English-language writers Agatha Christie and William Shakespeare.

While some classics can be something of a pain to slog through, Twenty Thousand Leagues Under the Sea holds up well.

Three strangers are each isolated by his or her own problems: Adaora, the marine biologist; Anthony, the rapper famous throughout Africa; and Agu, the troubled soldier. Wandering Bar Beach in Lagos, Nigeria’s legendary mega-city, they’re more alone than they’ve ever been before. But when something like a meteorite plunges into the ocean and a tidal wave overcomes them, these three people will find themselves bound together in ways they could never imagine.

Together with Ayodele, a visitor from beyond the stars, they must race through Lagos and against time itself in order to save the city, the world…and themselves.

“Chaotic, enthralling, and moving fluidly from character voices to oral-style narration to gut-punchingly beautiful prose.”
—NPR

I loved A Darkling Sea. It has aliens, intrigue, desperate missions, and it all happens underwater.

On a moon orbiting a gas giant, a human science station sits in pitch-black water. They’re studying a semi-primitive alien species, but when a dumb-ass scientist gets himself killed by the curious aliens, another alien species visits the science station and tries to take over. Chaos ensues.

“An impressive debut by a gifted writer.”
―Publishers Weekly (starred review)

Starfish is one of my favorite books.

A huge international corporation has developed a facility along the Juan de Fuca Ridge at the bottom of the Pacific Ocean to exploit geothermal power. They send a bio-engineered crew—people who have been altered to withstand the pressure and breathe the seawater—down to live and work in this weird, fertile undersea darkness.

Unfortunately the only people suitable for long-term employment in these experimental power stations are crazy, some of them in unpleasant ways. How many of them can survive, or will be allowed to survive, while worldwide disaster approaches from below?

“[P]art undersea adventure, part psychological thriller, and wholly original.”
—Booklist