Actor Bill Skarsgård had a moment of clarity playing Pennywise, the scary clown in the new movie of Stephen King’s It, when he walked into a scene full of unsuspecting child extras. “Some of these kids got terrified and started to cry in the middle of the take, and then I realised, ‘Holy shit. What am I doing? … This is horrible.’”

That was kind of the idea. Endangered children are one of society’s prime fears, and many a modern horror centres on either scared kids or scary kids – ideally both (see Annabelle: Creation). There’s plenty more to come: It will be followed by season two of the tonally similar Stranger Things, both of which revolve around preteens in peril. But the real horror for Hollywood’s kids is often to be found off screen.

In the early days, child performers were basically treated like cattle. To get those innocent little faces streaming with tears, directors had to cut a few corners. Shirley Temple spoke of being shut in a soundproofed black box when she misbehaved on set in the 1930s, while director Norman Taurog got his nephew, Jackie Cooper, to cry in Skippy by telling him they’d just shot his dog. Otto Preminger famously shouted “Cry, you little monsters!” at his child extras on Exodus before telling them their mothers had abandoned them.

Too close for comfort? The trailer for It.

Things have moved on, mercifully. Angelina Jolie recently had to frantically rebut a Vanity Fair story alleging she’d wrung the tears from her young Cambodian auditionees by giving them money then pretending to take it away again. (Vanity Fair released a statement saying they stand by the story as published).

But there are still real-life monsters stalking Hollywood, even if the industry doesn’t like to admit it. Another woman recently accused Roman Polanski of sexual assault, while Amy Berg’s 2014 documentary An Open Secret detailed child sex abuse in Hollywood circles and suggested it was the tip of an industry-sanctioned iceberg.

Many former child stars backed this up. The late Corey Haim revealed he was raped on a Hollywood set aged 11, while Corey Feldman spoke of his own “molestations”. In 1988, director Victor Salva was imprisoned for sexual misconduct with his 12-year-old star while making Clownhouse, a horror about – you guessed it – scary clowns terrorising children.

That’s not to suggest there is anything dodgy about It, Skarsgård’s traumatising turn aside. But given this history, Pennywise the creepy clown takes on an altogether more sinister aspect. Rather than some unfathomable supernatural evil, he could represent something much closer to home.

It is released on 8 September