There are some science fiction and fantasy worlds for which one book just isn't enough to keep a reader satisfied. Then again, not everyone has time to read a series that includes a dozen follow-ups. That's why duologies are the perfect sweet spot for readers who want to dive deeper into other worlds without getting overwhelmed.
Whether you crave post-apocalyptic triumphs of science and religion, or have a hankering for dragons, werewolves, demons, and more, here are some amazing and complete science fiction/fantasy duologies that you can read right now.
Operation Chaos and Operation Luna
In Operation Chaos, werewolf Steve Matuchek and formidable witch Virginia Graylock are partners in a war against the invading Caliphate forces. With America at stake, Steve and Ginny must stop their enemy from releasing a genie superweapon.
In Operation Luna, Steve and Ginny have found some normalcy by settling into a marriage and having three high-energy children.
But the couple is called to arms once again when a plot to sabotage America's first crewed mission to the moon is uncovered. The pair can't take on the threat on their own, however, and will have to rely on a group of magically-gifted allies to get the job done.
Want more great books? Sign up to get the best in sci-fi and fantasy sent straight to your inbox!
Silver in the Wood
If you love dark fairytales about old forests and the fae that lurk within them, you should check out the two novellas that make up The Greenhollow Duology by Emily Tesh. The first part, Silver in the Wood, introduces the reader to Tesh’s deliciously evocative writing, as well as the tender love that blossoms between Henry Silver and Tobias. The sequel, Drowned Country continues their queer tale in a tantalizing blend of folklore and wild magic.
The Risen Empire
The Risen Empire is a smart sci-fi novel set in a distant future, ruled by a massive galactic empire, filled with interesting technological details, including advances in AI and cryogenics. Westerfield’s prose is tight and engaging, brimming with multiple POV chapters and plot twists. Overall, it's an underrated and excellent read—and the story continues in The Killing of Worlds, the second part of Westerfield’s Succession duology.
The Dragon Series
Dragon's Winter follows Karadur, the son of a shape-shifting Dragon king. Karadur is destined to become a dragon and rule the kingdom of Ippa, but in a fit of jealousy, his twin brother Tenjiro stole the talisman that would manifest Karadur's true form.
As his brother threatens to destroy Dragon Keep, Karadur must rally his dragon warriors to vanquish the sorcerer and reclaim his destiny.
In Dragon's Treasure, Karadur unleashes vengeance and justice after a gruesome murder. He wipes out the outlaw Unamira clan—yet two members survive the attack.
As Karadur takes one survivor as his lover to maintain his family line, the other will grow into the life of crime he was destined for.
Santiago
The Santiago books are perfect for lovers of science fiction and space operas, packed with action, surprises and larger-than-life characters. There’s Santiago (also known as the Songbird) who is an infamous bounty hunter, Virtue Mackenzie, a freelance reporter struggling to land an interview with the Songbird, and the Swagman, a highly determined art collector … to put it mildly. Not only is Resnick’s worldbuilding absolutely top-notch, but the books are a lot of fun—especially if you’re looking for a Wild West adventure set in outer space.
Six of Crows
Six of Crows and Crooked Kingdom form an exciting duology set in Leigh Bardugo’s Grishaverse world that focuses on a ragtag team of street urchins who manage to pull off impossible heists, get revenge on those who wronged them, and find ways to be there for each other. If you liked Sanderson’s first Mistborn book or enjoy YA fantasy novels, or have a soft spot for found family narratives, then the team of Crows are sure to welcome you into a marvelous and terrifying world.
Love in the Ruins and The Thanatos Syndrome
In Love in the Ruins, the United States teeters on the edge of catastrophe. Is the country's last hope Dr. Thomas More, an alcoholic psychiatrist?
For all his faults, he's invented the lapsometer, a device which diagnoses and cures the country's spiritual ailments. In the wrong hands, it could destroy the very fabric of society.
In The Thanatos Syndrome, Tom has plans for a simpler life back home in Louisiana. But when the inhabitants of his hometown start spiraling out of control, Tom and his cousin Lucy—an epidemiologist—must take a deeper look into the situation. What the pair finds is a conspiracy by the government to rob its citizens of their very selves.
Earthseed
This duology from one of the most prescient authors in science fiction begins with Parable of the Sower. Following an economic and ecological apocalypse, Lauren Oya Olamina escapes the slaughter which claims her family and the majority of her community.
Alongside a group of survivors, Lauren travels north through America's wasteland. But danger is lurking around every turn as this courageous teenager births a new religion which embraces change and survival.
In Parable of the Talents, the religion of Earthseed has taken root in a resilient community, but a despot poses a new threat to the future Lauren forged.
The New Springtime
In At Winter's End, the final remaining inhabitants of Earth have spent millennia living underground to escape the falling "death stars" which wiped out their civilizations. Now, the Earth's surface is once again habitable. A leader of one of the underground tribes forges a path to freedom, but what awaits them is full of danger.
In The Queen of Springtime, Earth's underground survivors have made it to the surface to repopulate and reclaim the legacy they left behind. But another race claims the surface—insect-like beings called the hjjk—and they aren't looking to return the land they spent eons calling home.
In the Shadow of the Fall (Guardians of the Gods Book 1)
Tobi Ogundiran’s epic fantasy novellas are gorgeously crafted and steeped in Yoruba myth and tradition. The first book, In the Shadow of the Fall, focuses on Ashâke, a failed acolyte who is determined to summon the orisha—and she soon finds herself embroiled in a cosmic war. The soon-to-be-released sequel, At the Fount of Creation, deepens the worldbuilding, throwing light on the feuds between the gods and the godkillers, even as Ashâke strives to do the right thing. If you’re looking for shorter reads that are engrossing and enjoyable, you’ll love Ogundiran’s works.
Alice's Adventures in Wonderland
You can never go wrong with the classics. A childhood favorite, Alice’s Adventures in Wonderland in many ways set up the foundations of the portal fantasy genre. Young Alice follows a white rabbit down a hole and stumbles upon Wonderland—a fantastical world filled with strange and whimsical creatures, where nothing is what it seems. Alice gets to revisit Wonderland a second time—this time by falling through a mirror—in Through a Looking Glass, filled with more adventures and delightfully nonsense rhymes such as the “Jabberwocky”. Accompanied by John Tenniel’s gorgeous illustrations, both books are collectors’ items that can be read time and time again.
Slayer
This duology takes place in the world that Buffy the Vampire Slayer left behind. Slayer follows twins Nina and Artemis, who were raised at the Watcher's Academy. Their whole lives they've been trained to be guides to future Slayers—those gifted with supernatural strength to fight the forces of darkness.
But Nina has never wanted this violent life, preferring instead to follow her dreams to be a medic. Things don't go according to plan when Nina rises not only as the next Slayer, but the very last one.
In Chosen, Nina hopes that the Watcher's Castle will be a utopia for battered demons. But Nina's slayer powers don't feel quite right after a run-in with an evil succubus. As she battles an inner darkness, an outer threat promises to strike close to home. With Slayers, it's always another apocalypse.
Semiosis
Sue Burke’s debut novel, Semiosis, is a familiar story of first contact where human colonists landing on a strange planet have to find innovative ways to survive the hardships as well as contend with an alien presence. It’s a careful exploration of what it means to confront the unknowable and inexplicable—suited for fans of character-driven adventure and shows like Scavengers Reign. It’s followed by a sequel, Interference, set on the same planet, about 100 years after the events of the first book.
One Dark Window
The first part of Rachel Gillig’s The Shepard King duology is premised on a unique magic system based on Tarot/oracle cards (called Providence cards here), appealing to readers with a taste for Gothic aesthetics and darkly romantic storylines. It unfolds the story of Elspeth Spindle and her relationship with Ravyn, the King’s nephew—together they must gather the twelve Providence cards before The Nightmare is unleashed. But one card is still elusive, so their tale continues in Two Twisted Crowns in which Elspeth must finally confront the monster that’s been sharing her head.
Shatter the Sky
Maren grew up amidst the ruins of a conquered mountain nation. Now, she wants only to have a peaceful life with her girlfriend Kaia. But one day Kaia is kidnapped by a prophetic band of agents called the Aurati, and forced into their ranks.
Maren plans to steal one of the emperor's dragons and storm the Aurati base. But that's easier said than done, as Maren must first become an apprentice to the Aromatory—the emperor’s dragon trainer.
In Storm the Earth, Kaia isn't the same person she was before her abduction. Not to mention, Naava has isolated to recover from devastating wounds, leaving Maren in charge of freeing the rest of the dragons on her own.
This Savage Song
In This Savage Song, Kate Harker and August Flynn are heirs to a divided city overrun by monsters and torn apart by war.
Kate longs to be like her father, who charges humans for protection from the monsters he lets roam the streets. August craves humanity, but he's a monster who can snatch a human's soul with one simple song. Kate and August are thrown together with the fate of their home hanging in the balance, and faced with the choice to become true heroes or villains.
In Our Dark Duet, the war between monsters and humans rages fiercely on. August and Kate must battle a demon from their past, and their preconceptions about each other.
The Priory of the Orange Tree
If you’re longing to get swept up in an epic tale spanning over eight hundred pages, filled with courtly intrigue, magnificent dragons, and a soft sapphic love story, pick up a copy of The Priory of the Orange Tree ASAP. It’s an engaging tale focusing on the storylines of a queen struggling to hold onto the reigns of power, a handmaiden who’s secretly a spy and a young girl whose dreams of being a successful dragon rider are tragically dashed—and yet all three have to find a way to move on and confront the new evils that are rising from their sleep.
Inspired by a mixture of history and legend, The Priory of the Orange Tree is a hefty but satisfying read. Shannon also revisits this world in A Day of Fallen Night, a prequel novel that’s similarly multi-layered and engrossing—though both books can also be read as standalones.
Wintersong
If The Labyrinth and The Phantom of the Opera had a lovechild, it would be Wintersong, a lush and enchanting fantasy that narrates the story of strong-minded Liesl who journeys into the Underworld to rescue her sister abducted by the Goblin King—only to slowly fall into the trap of love herself.
There’s a beautiful musical cadence to the author’s prose, along with a sexy forbidden love story in the latter half, making it an indulgent and haunting read. And if the ending leaves you hungry for more—there’s a sequel, Shadowsong that continues the story of Liesl’s musical career and her tryst with the enigmatic Goblin King.
Want more great books? Sign up to get the best in sci-fi and fantasy sent straight to your inbox!
Featured image from the cover of ‘Storm the Earth.’