Stephen King wouldn’t still be in business if all he had to sell was fear.

Within every terrifying story about a shape-shifting killer clown , homicidal father in a haunted hotel or super flu that depopulates the planet , the relentlessly prolific writer has filled his pages with equally powerful supplies of strength, selflessness and even hope. That may be why so many readers, many of whom discovered his books when they were kids themselves, have remained loyal over 45 years of storytelling.

The author is about to turn 72 as he publishes his 61st novel , “The Institute,” about children who display supernatural abilities being forcibly rounded up for study by a shadowy organization that brutally discards them when their usefulness is exhausted. Those who think of King primarily for horror may be surprised by how much warmth there is in a book that sounds so coldblooded.

The concept for the book dates back more than two decades, when King — who has depicted similar psychic characters as loners in books such as “Carrie,” “The Shining,” “Firestarter” and “The Dead Zone” — pictured an entire schoolhouse filled with such kids. When he began writing the book in March 2017, he thought of it not as a horror story but as a resistance tale, with 12-year-old telekinetic genius Luke, teenage mind reader Kalisha and 10-year-old power-channeler Avery forming a rebellion inside their detention center.

“I wanted to write about how weak people can be strong,” King says, speaking by phone from his home in Bangor, Me. “We’re each on our own island, and at the same time sometimes we can yell to each other and get together, and there is that sense of community and empathy. I love that. I love that in stories.”