4 Fantasy Books No One Guessed Would Spawn Blockbuster Series

Fantasy books have exploded in popularity alongside TV shows and movies over the last couple of decades. However, most still don’t break into the mainstream in any significant way, much less go on to spawn blockbuster series. Certain authors command excitement with every new release, including Brandon Sanderson and Sarah J. Maas. Several of the writers on this list are also instant bestsellers now, but no one originally guessed their novels would spin out into massively popular series.

It’s often a pleasant surprise when that happens, signaling that a fantasy story has a broad appeal — and proving that the category isn’t incapable of drawing a wider audience. That’s becoming truer as time goes on, and it’s leading to more fantasy adaptations as well. These four novels either have one or are in the process of getting one, despite the fact that no one thought they’d become such hits. Now they’re blockbuster titles even non-readers and non-fantasy fans recognize. They prove it’s often worth taking a chance on an unknown story with great potential.

4) A Game of Thrones by George R.R. Martin

George R.R. Martin is a household name and would easily sell any new release at present — especially if he were to drop the long-delayed Winds of Winter. However, there was a time when Martin’s career was a less sure thing. His early novels didn’t see the success that A Song of Ice and Fire would come to command. And even A Game of Thrones took more than a decade to finally hit the New York Times bestseller list, only doing so ahead of HBO’s TV show in 2011.

The sequels got traction before the adaptation, likely contributing to HBO’s desire to recreate the story in the first place. It crossed over from a beloved recommendation in fantasy spaces to a mainstream phenomenon when Game of Thrones blew up. And seeing the impact the story has had on the genre since, it’s hard to imagine it not being a blockbuster in hindsight. It’s often used as the bar for good fantasy, but when A Game of Thrones first released in 1996, no one could have predicted it would become such an influential tale.

3) Fourth Wing by Rebecca Yarros

Romantasy is having a moment in the spotlight in the 2020s, but there are two series that stand out as the loudest and clearest successes: A Court of Thorns and Roses and Fourth Wing. The former had Sarah J. Maas’ previous success with Throne of Glass to build on, but Fourth Wing was a more surprising sensation. It went viral on TikTok and climbed the bestseller list quickly following its 2023 release. These turns were made more shocking by the book marking Rebecca Yarros’ first foray into fantasy. She’d established herself as a trusted romance writer beforehand, but no one could’ve foreseen the mainstream success of her romantasy experiment.

Looking at what types of romantasy and fantasy romance stories appeal, perhaps it shouldn’t be a surprise that Fourth Wing expanded into one of the 2020s’ biggest book series. Its use of shadow daddies, dragons, and a light enemies-to-lovers bond all contributed to its success. Of course, there are just as many fantasy and romantasy books with those elements that didn’t spawn hugely anticipated sequels like Iron Flame and Onyx Storm. And the series will likely only get bigger as it delivers its final two sequels.

2) Dungeon Crawler Carl by Matt Dinniman

Dungeon Crawler Carl blends sci-fi and fantasy, bringing both genres to more mainstream audiences thanks to its recent virality. The LitRPG novel and its sequels have positively exploded in popularity over the last few years. That’s likely to continue with the upcoming Dungeon Crawler Carl TV show in the works. Its first (and best) casting announcement already accumulated tons of hype, so it’s easy to envision how much excitement will surround the show when it finally debuts. And considering the books’ willingness to unpack topics like corporate greed, ethical entertainment, and the compromises that accompany survival, it’s no wonder that the series has hooked so many.

Yet Dungeon Crawler Carl was far from an instantaneous success. The first book was self-published back in 2020, and it took time for it to become a smash hit. It even had several sequels before it really blew up, so no one saw the shift from cult favorite to must-read series coming. It’s a good thing it has exploded, though, as it means we’ll soon have a screen rendering of this story to enjoy. It just goes to show that patience can pay off when awaiting a truly great series’ triumph.

1) Harry Potter and the Sorcerer’s Stone by J.K. Rowling

Perhaps the best-known example of an unexpected fantasy book becoming a massively successful series is Harry Potter and the Sorcerer’s Stone. It was J.K. Rowling’s first published book, so it had no name power behind it at the time of its release. And because it was a children’s fantasy story, it wasn’t expected to go far, even if it succeeded with its target audience. Looking back, it’s laughable to think that Harry Potter would only resonate with younger readers, as the series has since gone on to accumulate fans in all age groups. It’s also demonstrated surprising staying power, with the children who grew up with it still returning to it decades later.

In addition to spawning a mega-popular fantasy series, Harry Potter and the Sorcerer‘s Stone also resulted in a larger cinematic universe. The Harry Potter and Fantastic Beasts movies capitalized on the story’s success, and HBO’s reboot is poised to do the same later this year. You’d be hard-pressed to find anyone who hasn’t heard of the Boy Who Lived, even if they themselves don’t appreciate his story. Growing up with ’90s fantasy, it was unimaginable a series like this could reach such heights.

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