The "Creepy" True Story Behind 'The Whisper Man', Netflix's Terrifying New Thriller

Things are growing colder, grimmer, and a lot more unsettling on Neflix.

The streamer's latest prestige nightmare is The Whisper Man, a claustrophobic detective series starring Robert De Niro as the wizened ex-sleuth dragged back into mystery-cracking when his eight-year-old grandson is abducted. The boy’s father, Tom (Adam Scott), is De Niro’s estranged son.

Cue a Freudian bonanza of complicated father-son dynamics and awkward "you-weren't-there-when-I needed-you-mosts" as the fractured men soon unearth a connection between the disappearance of the boy and a closed case of a convicted child murderer called The Whisper Man—a killer who De Niro’s DI Pete Willis once put behind bars 30 years ago. But now, apparently, he’s killing again.

At one point, another detective (Michelle Monaghan) reads a note in child’s handwriting:

If you leave the door half open, you’ll hear the whispers spoken. If your window is left unlatched you’ll hear him tapping at the glass. If you’re lonely, sad and blue, the Whisper Man will come for you.

This begs the question one must always ask when Netflix puts out an original feature: is it based on a true story?

The answer is, sort of. Well, it’s based on a bestselling book by the super-author Alex North, and according to him, the idea – as all the best ones do – came from a real-life experience with his son.

“When I first started [the book], I wanted to write about fathers and sons, and that was the key thing for me,” North told Digital Trends. “I had just become a father myself, but I didn’t quite have the way into it to make it into a crime thriller.”

But then he noticed his son – by then four – saying creepy things to the floor.

“I was in the kitchen, and I heard him playing in the front room, so I kind of poked my head around the kitchen door to say, ‘What are you doing?’ And he said, ‘Oh, I’m just playing with the boy in the floor,’ which gave me a little bit of a chill.”

He later told Australia’s Better Reading blog: “I’ve always loved reading threads of creepy things that children can say, and I knew then that the boy in my story would have imaginary friends like that, and that a few of them might turn out to be more than they seemed.”

Much of his inspiration, he says, comes from online parenting forums where mothers and fathers discuss the creepy things their children say. “Like saying “that’s where I used to live” when the family is driving past a graveyard,” North told Celadon Books, “or talking about the man with the long neck in the closet and then the parents discover someone hung themselves in the house years earlier.”

These were the kernels that sprouted the idea for a book that would become an international phenomenon.

This story originally appeared on Esquire.com.