A 13-year-old magician and a student council president inadvertently disrupt the space-time continuum in Carlos Hernandez's middle grade breakout, Sal and Gabi Break the Universe. Set in Miami in the near future, the novel is the fourth book in the Rick Riordan Presents line from Disney-Hyperion, which specializes in middle grade fantasies that integrate world folklore and mythologies. In this case, Hernandez draws on his Cuban background and seamlessly mixes sci-fi and supernatural elements with typical middle school problems, such as bullying and schoolwork. Sal, for instance, is able to conjure objects out of nowhere and even reach into an alternate universe to bring his dead mother back to life; this is not your typical tale of cafeteria drama.

Pairing the fantastical and the ordinary feels perfectly natural to Hernandez. "Life is complicated, plotless, shocking, and unpredictable," he says. "It doesn't wait for the ‘right time' to drop a tragedy in your lap, or joy, or beauty, or a difficult choice."

Sal and Gabi Break the Universe finds Gabi Real and Sal Vidón in middle school, but Hernandez based them both on adult characters he had previously written about. "Sal," he says, "appears as a grown-up theoretical physicist in a short story called ‘The Assimilated Cuban's Guide to Quantum Santeria,' " published in a collection of the same name. The adult version of Gabi also appears in Hernandez's short fiction. "She's a journalist," he says, "and her beat is the cryptic and the fantastic—unicorns, uploaded brains, that sort of thing." Hernandez liked them so much, he wanted to get to know them as kids, too.

Serendipitously, it was by way of The Assimilated Cuban's Guide to Quantum Santeria that Rick Riordan, author of the Percy Jackson series, found Hernandez. Riordan gave the story collection a Goodreads review—which was, needless to say, quite a boon for a rising author—and reached out to Hernandez to see if he had considered writing for kids. "So, here's the deal," Hernandez reflects. "I don't get to win Powerball. I used every drop of luck I had in order to be found by Rick."

It's important to Hernandez to create diverse characters who face challenging realities that might resemble the lives of his readers; Sal and Gabi are Cuban-American, and Cuban Spanish appears throughout the novel. But Hernandez believes diversity in literature has an even grander role to play. "The function of diversity in books, whether fiction or nonfiction, is to diversify your mind," he says. "Readers are drawn to expanding their understanding of the human condition. But they also crave the way that reading evokes connection, fellow feeling, and even love, across space and time, via our imaginations."

Hernandez is planning more adventures for Gabi and Sal, who become much more accustomed to manipulating space-time. The next book is called Sal and Gabi Fix the Universe, and they do, "kind of," Hernandez says. "They also break it some more."