Thanks to HBO’s landmark adaptation of A Song of Ice and Fire that’s better known as Game of Thrones, author George R.R. Martin has become a legend in modern popular culture. Before publishing the first chapter of Westoros’ epic history in 1996, Martin was primarily known for writing Science-Fiction and Horror stories that are just as intriguing and compelling as a Stark’s adventures.

But as interesting and well-received as some of these books may be, not all of them could be adapted like Game of Thrones was. Whether this is because of the story’s massive scale or other factors, here are 10 books written by George R.R. Martin that would be impossible (or at least very difficult) to adapt today.

Fevre Dream

Bored seafarer Abner Marsh gets the deal of a lifetime when the mysterious traveler Joshua York commissions him to captain The Fevre Dream, the greatest steamboat ever made. Things seem to be going great for Abner except for one thing: Joshua is a thousand-years old vampire.

Of the stories listed here, Martin’s reflective take on vampire fiction is the most plausible for a live-action adaptation. The only problem is that vampire movies are a bit passé today following the subgenre’s oversaturation in the early 2000s, making the case for a new vampire movie a bit difficult.

Tuf Voyaging

Tasked with terraforming entire planets and remaking their ecologies, the reclusive and no-nonsense genius Haviland Tuf and his psychic cat Mushroom search the galaxy for planets and solar systems to discover, visit, and reshape.

While the idea of Star Trek starring Spock may sound discouraging to some, there’s a nice audience out there waiting for more meditative sci-fi stories like Arrival or Annihilation. But because that target audience is rather small, it’s unlikely that a major studio would finance a galactic procedural anthology such as Tuf Voyaging.

The Ice Dragon

Often mistaken for being a part of the world of A Song of Fire and Ice because of its frosty eponymous creature, Martin’s novella followed Adara when she meets the best friend she could ever ask for: an ice dragon. This is also Martin’s debut into children’s fiction.

The Ice Dragon is basically Dragonheart or The NeverEnding Story but told by the guy who dreamt up The Red Wedding. There’s nothing bad about this fairytale, but it’s too similar to older movies that already told the premise well. It could, however, work as an animated feature on Netflix.

Sandkings

When businessman and exotic animal aficionado Simon Kress gets bored of his current pet collection, he finds enjoyment in his newest addition: the Sandkings. Though they treat him like a god at first, they become murderously uncontrollable when get sick of his abuse.

If Gremlins removed all of the comedy, Sandkings would be the outcome. It’s because of this similarity that this particular horror story won’t be adapted any time soon – especially since there are rumors of a third Gremlins being in development.

Windhaven

In a world of storms and islands, the young Flyer Maris of Lesser Amberly sets out to change the unjust world she lives in. But as the years pass, she learns that reform isn’t as utopian as she hoped it would be.

If Windhaven were optioned during the height of the Young Adult Dystopian’s popularity, it wouldn’t have been able to stand out. Now that the genre’s dead, there’s currently little hope for Maris’ story to come to life. That, and her adventures may remind people a bit too much of a certain notorious bomb named Waterworld.

Dying of the Light

Set on the planet of Worlon, the story focuses on Dirk t’Larien when he visits the (literally and culturally) dying planet to answer his former lover’s request. Learning that his ex Gwen is trapped in an abusive marriage, Dirk goes to save her even if it means driving Worlon further into the brink.

There’s a current need for new space operas that another Star Wars installment can’t fill, but this novel may not exactly be the best candidate. Basically Game of Thrones set in space, Martin’s debut novel is too large in scale to adapt into live-action.

In The House Of The Worm

This collection of novellas and short stories can be described as H.G. Wells’ The Time Machine mixed with H.P. Lovecraft’s Cthulhu Mythos, with the cast of characters starting out on a journey for revenge only to meet the horrifying subterranean truth behind their ancestral religion.

The narrative and themes of Martin’s send-off to Lovecraftian lore would make for ambitious entertainment, but there’s a reason why none of Lovecraft’s most famous stories haven’t been adapted. Studios tend to avoid existential horror like poison, so a tale about the Legendary White Worm simply won’t fly.

A Song For Lya

Following the telepathic explorers Rob and Lyanna when they visit the mysterious planet of Shkea, the two stumble upon a strange religion filled with human converts. To their horror, the sect’s god isn’t a mythical figure but a physical Eldricth monstrosity.

Much like In The House Of The Worm, a book about an existentially horrifying religion would be an unlikely story for studios to pick up. If something as iconic as Lovecraft’s At The Mountains Of Madness has been languishing in development hell for years, imagine how difficult it would be to adapt Martin’s religious horror about a giant parasite.

The Armageddon Rag

Aging journalist and former hippie Sandy Blair finds the case of a lifetime when an infamous rock band promoter is found brutally murdered. Nazgul, the band at the center of it all, may be using its music to bring about the apocalypse.

Not only is the concept of rock music being evil (or at least being intertwined with the supernatural) outdated but the book is considered to be Martin’s worst. Even Martin himself acknowledges its failings, though he’s still proud of giving his experimental writing a shot. It’s unlikely that any studio would adapt the celebrated author’s weakest tale.

The Real Song Of Ice and Fire

HBO’s former pride and joy Game of Thrones was mostly based on Martin’s A Song of Ice and Fire, directly adapting most of the first four books before diverging from the source material and leaving out the upcoming The Winds of Winter and A Dream of Spring.

But thanks to an abysmal eighth season that tanked the show’s critical and audience appeal, Game of Thrones’ reputation has been forever tarnished. While HBO will still air the prequel, it will be years before someone revisits Martin’s magnum opus to adapt it with the respect it deserves.