Before I was an author, I worked in Hollywood as a film producer and development executive for almost a decade. My jobs ranged from my first gig working for Michael Bay’s genre company Platinum Dunes, where we launched with the remake of The Texas Chainsaw Massacre, to New Line Cinema during the height of The Lord of the Rings juggernaut. My then boss, Mark Ordesky, was the executive producer and one of the masterminds behind bringing the Tolkien classics to the screen with vision, respect, and ultimately, massive financial and critical success.

“It’s easier to sell a true story than a novel, but the key to everything is to have an exciting narrative,” says my friend and writer Scott Andrew Selby (author of Flawless and A Serial Killer in Nazi Berlin), who has several book-to-film adaptations in the works. “Just remember when celebrating a film option, there’s a long and perilous journey to seeing your book on the big screen.”

My debut novel The 13th Continuum, the first book in my Continuum Trilogyis being packaged into a feature film. Of course, that’s super exciting, but there’s always the danger that the film adaptation won’t do the book justice. As readers, we all know what that disappointment feels like. I’ll never forget seeing Jurassic Park on opening day at the Salem Valley 8 in my hometown of Roanoke, Virginia—and feeling so let down by the film. At that time, the big changes from the book really rubbed me the wrong way. I’ve since come to appreciate Spielberg’s interpretation and overlook the lapses. Interview with the Vampire is another one that leaps to mind as disappointing, despite the killer A-list cast.

Here are my tips for a successful book-to-film adaptation:

1) Shape the arc

Books can get away with being episodic sometimes, while movies cannot. The film version needs to build to an exciting and satisfying climax that delivers for an audience. The narrative from the book may need to be shifted or shaped to accomplish this goal, so don’t be afraid to make changes from the original work.

2) Keep the magic that made the books work

Changes will certainly need to be made, but don’t lose the magic that made the book special. In making The Lord of the Rings films, often people forget how many changes we made to the narrative in the books (removing characters and whole side journeys, shifting ending points and shaping climactic battle scenes). That’s because we always kept the integrality of the books in mind.

3) Casting, casting, casting

This is one of the keys for adapting a book—finding the right actors to bring the beloved literary characters to life on the big screen. Sometimes, it works out well. The Twilight films were cast perfectly. You can tell by the fans’ reaction to them. But other times, when a film is miscast, the outcry can be deafening and ruin the film.

4) It’s really all about the filmmaker

Of course, the script is important, but the director is the person who will really bring the vision to life. Who can forget when Alfonso Cuaron took the helm for Harry Potter and the Prisoner of Azkaban? In my humble opinion, the third film is when the world really came to life. Ditto for Francis Lawrence taking over The Hunger Games franchise. Suddenly, the world felt sweeping, magical, and real. Before these filmmakers came on board, the films paled compared to the books. I was a big fan of both filmmakers for years before they stepped onto these blockbuster projects (I simply adored the little-watched Constantine).

I can’t wait to see how my books get adapted—and especially what filmmaker comes onto the project to bring them to life. My second book Return of the Continuums expands and builds out my world, while The United Continuums (July 11, 2017) completes my epic trilogy. As the books gain more fans and grow in reach, it only helps the film prospects. Keep your fingers crossed for big screen magic!