When it comes to tearjerkers, “A Monster Calls” reigns supreme.

Seriously. Few movies in recent memory have so expertly turned on the waterworks, while still being genuine and natural about it. Even a screening of the film — which is now in theaters — for critics and journalists was marked by intense, audible sobbing.

“My first approach to the story was through the book and I had the same kind of emotional reaction. It’s a very emotional story,” filmmaker J.A. Bayona says of his adaptation of Patrick Ness’ novel. “What I thought was very interesting was the fact it’s a fantasy film about a young kid. It’s so rare nowadays to find this kind of material in fantasy, dealing with emotion and treating it with so much respect.”

The filmmaker draws out the Spielbergian qualities of the story, which concerns a lonely English boy named Conor O’Malley (Lewis MacDougall), who copes with the terminal illness of his mother (Felicity Jones) by forming a bond with a tree monster (Liam Neeson, in motion capture) that tells him allegorical stories to help Conor through his struggle.

“The story about the relationship between a kid and a monster who’s trying to help him to cope with a situation he’s going through, using stories, somehow it’s also about how we use fantasy to understand reality,” Bayona says.

Bayona, 41, a Spanish director whose past works (the horror movie “The Orphanage” and the tsunami drama “The Impossible”) similarly combine sweeping genre spectacle with rich emotions, will next head to the “Jurassic Park” franchise for the 2018 sequel. The expectations for his work and standards applied to it will be the greatest they’ve ever been. But one fundamental principle sustains him:

“This is such an important part of our education, how we need stories, how we need to read books, watch movies, to have a better comprehension of life,” he says.