"The Strange Ones" (1963) is a short film in the classic genre of stranger-danger movies. It presents a nightmarish world populated by stalking pedophiles (they look like anyone else!) and risk-seeking children.
As Jesse Walker observes,
because of the sheer nightmarishness of it... the shadows, the creepy music, the narrator who constantly wanders into horror-movie territory.
It's on YouTube for your instructional pleasure:
The film avoids the classic Gothic trope of family horror, instead showing danger as solely the province of strangers. This is statistically weird, since the greatest number of attacks on children come from family members. Naturally it lets the film cast family members in a salvific way... even though the framing plot is based on a girl not heeding her parents' instructions. Unless the parents failed to teach her properly. Bad parents.
The strong arm of the law is a child's best protection in this movie. The plot kicks off with a brief police dragnet, then consists mainly of a policewoman explaining to a child the Gothic hellscape in which she lives. Note the implements of violence literally backing up the officer:
The law will save you!
One intriguingly Gothic part is "Strange Ones"' admonition to avoid "deserted places". This makes for a creepy, Ballardian scene, with a pedophile stalking a boy across a postindustrial zone: