Author Rick Riordan said the film contract he signed gave him no creative control or final cut privileges on the adaptation of his popular book series.

20th Century Fox released “Percy Jackson & the Olympians: The Lightning Thief” in theaters February 2010 with hopes of starting a new “Harry Potter”-sized film franchise. The family epic was even directed by Christopher Columbus, who launched the “Potter” franchise with “Sorcerer’s Stone” and “The Chamber of Secrets.” Unfortunately for Fox, the “Percy Jackson” franchise only lasted two films, neither of which made it to the $250 million mark worldwide.

“Percy Jackson & the Olympians: The Lightning Thief” was based on the teen novel “The Lightning Thief,” written by Rick Riordan. The author recently posted on his official website a lengthy blog post in which he detailed the struggles he faced in pleading with the film’s producers to make the first movie as faithful to his book as possible. Riordan said that his contract for the film left him with little creative control or final say about the movie adaptation, which resulted in problematic changes he feared would kill the potential film franchise.

Riordan sent an email note to producers in January 2009 after he heard the ages of the main characters were being changed from 12 years old to 17. “As no one wants to see this film succeed more than I do,” the author wrote, “I hope you’ll let me share a couple of reasons why this is a bad idea from a money-making point of view.”

“First, it kills any possibility of a movie franchise,” Riordan explained. “The series is grounded on the premise that Percy must progress from age twelve to age sixteen, when according to a prophecy he must make a decision that saves or destroys the world. I assume [Fox] would at least like to keep open the option of sequels assuming the first movie does well. Starting Percy at seventeen makes this undoable.”

Riordan also argued making Percy older for the movies would alienate the core audience. “The core readership for Percy Jackson is age 9-12,” he wrote in the email. “There are roughly a million kids that age, plus their families, who are dying to see this film because they want to see the pictures in their imagination brought to life. … They are keenly aware that Percy is twelve in the first book. By making the characters seventeen, you’ve lost those kids as soon as they see the first movie trailer.”

While producers didn’t end up starting the film with Percy being 17 years old, they also didn’t listen to Riordan. The movie stars Percy as a 16-year-old, played by Logan Lerman. Riordan sent another email to producers in March 2009 after he was allowed to read Craig Titley’s full script.

“The script as a whole is terrible,” Riordan wrote after naming some of the things he did like about the film. “I don’t simply mean that it deviates from the book, though certainly it does that to point of being almost unrecognizable as the same story. Fans of the books will be angry and disappointed. They will leave the theater in droves and generate horrible word of mouth. That is an absolute given if the script goes forward as it stands now. But the bigger problem is that even if you pretend the book doesn’t exist, this script doesn’t work as a story in its own right.”

Riordan went on to detest the film’s dialogue for pandering to teens in a false way. “There is nothing radical, fresh or interesting about biyotch, ass, or shit,” he wrote. “[This language] has been overused to the point that it doesn’t even rate a cheap laugh anymore.” The author also took issue with the script’s attempt to make the story edgier and thus more appealing to older teenagers.

“I’m talking with fourth and fifth graders all the time about this upcoming movie,” Riordan wrote. “I would be horrified if I steered them into a movie with this kind of content. I wouldn’t see it. I wouldn’t let my kids see it. I wouldn’t recommend anyone else see it, and I certainly wouldn’t want my name associated with it. Please do not ‘sex up’ my children’s story.”

Riordan’s book series consists of five novels, a number the film franchise was never able to reach. The movie sequel, “Percy Jackson: Sea of Monsters,” opened in theaters August 2013 and was the final straw for the franchise. Head over to Riordan’s website to read more from his emails.

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