Tales and reports of feral children have long been a subject of fascination, from Tarzan to famed 18th-century French case study Victor of Aveyron to disturbing contemporary accounts of neglect. It’s virtually impossible to imagine surviving through such circumstances — and yet we try.

First-time feature director Andy Muschietti’s supernatural thriller “Mama” gets really out there in its speculating, wondering what if abandoned kids were watched over by an angry ghost. It’s a kooky scenario laid out with impressive creepiness at points, as Muschietti expands on a previous short film under the guidance of producer/genremeister Guillermo del Toro. The frustration, though, is how much the movie leans on made-ya-jump scares and contrived plot devices when its quieter chills and already fraught setups are so potent.