“Home Alone” meets “The Bad Seed” in “Better Watch Out,” a clever black comedy-cum-horror pic in which the apparent home invasion that traps a babysitter and her charges turns out to be something else entirely. This macabre Christmas movie, a co-production shot in Australia but set in Anytown USA, seems destined to become one of those Yuletide perennials for people who like their holiday-themed entertainment as perversely un-wholesome as possible. It’s already sold to numerous territories (including Well Go for North America) with an eye toward a seasonally appropriate late-2017 release.

Squabbling as usual before leaving for a dinner party, the Lerners (expert comic turns by Virginia Madsen and Patrick Warburton, seen again just briefly at the end) leave only-child Lukas (Levi Miller) in the care of Ashley (Olivia DeJonge). At age 12, you might expect Luke to chafe at still requiring a sitter. But in fact he has high expectations for the night with this very pretty teen who’s minded him for years now — absurd expectations, perhaps, of declaring his love and even consummating it.

When, after having sneaked some champagne, he duly commences such overtures, Ashley’s reaction is exactly as bemused and appalled as any grownup might expect. However, the awkward standoff is interrupted by mystery phone calls, signs of disturbance both inside and out the house, then finally a clear threat of menacing intruders.

It would be spoiling the first major surprise to reveal more, beyond noting that the rapidly escalating events soon involve Lukas’ geeky playmate Garrett (Ed Oxenbould), as well as luring Ashley’s current boyfriend (Aleks Mikic’s Ricky) and past one (Dacre Montgomery as Jeremy) into the mix. Phones and computers are conveniently disabled even before people starting being duct-taped to dining room chairs. What starts out looking like a prank run amuck gradually grows more sinister, with director Chris Peckover (“Undocumented”) nicely handling the swerves toward dramatic peril and fatal consequences while still maintaining a confectionary “family entertainment” veneer of antic doings in a glossy suburban setting.

A familiar suspension of disbelief is required by Zack Kahn and Peckover’s script — the kind that requires you accept that someone very young might already be a diabolical mastermind and that no one in their life would have noticed. But the slightly cartoonish air (from variably caricatured supporting roles to a soundtrack full of ironic Christmas cheer) enables that leap, just as the eventual grimly serious moments are impactful without straying into bad taste or cynical misanthropy.

Aussie thesp DeJonge of “The Visit” (sporting an American accent, like everyone here) provides grit and resilience as the principal victim, who never stops trying to re-assert her authority as the designated adult (or near-adult). Miller (from “Pan” and “Jasper Jones”) is quite startling as a seemingly ordinary brat whose precociousness gets ever more alarming. Many movies in this general realm fail because the juvenile actor can’t quite summon a full, convincing depth of malevolence. It’s surely a testament to this actor’s resources that eventually we can conceive of no fate too cruel for a character at once so monstrous and infuriatingly childish. Oxenbould and Mikic also impress, dimensionalizing smaller, potentially one-note roles.

Shot in a Sydney studio for a hyperreal, snow-globe look that subtly sends up more conventional Christmas movies, the film’s design contributions add up to a deceptively bright, cheerful widescreen package. Brian Cachia’s orchestral score likewise goes for a subversive effect by aping the sounds of mainstream family seriocomedies, though the content here is more grand guignol than “National Lampoon’s Christmas Vacation.” The now more cannily titled “Better Watch Out” was called “Safe Neighborhood” during its production and initial screenings last year.

Film Review: ‘Better Watch Out’

Reviewed at Seattle Film Festival, June 11, 2017. (Also in Fantastic, Sydney film festivals.) Running time: 89 MIN.

  • Production: (Australia-U.S.) A Well Go USA release (U.S.) of a Storm Vision Entertainment and Best Medicine Prods. presentation. (International sales: Versatile, Paris.) Producers: Sidonie Abbene, Brion Hambel, Paul Jensen, Brett Thornquest. Executive producers: Steven Matsuko, Shane Abbess. Co-producers: Matthew Graham, Matthew Jennison.
  • Crew: Director: Chris Peckover. Screenplay: Zack Kahn, Chris Peckover, from a story by Kahn. Camera (color, widescreen, HD): Carl Robertson. Editor: Julie-Anne De Ruvo (confirm). Music: Brian Cachia.
  • With: Levi Miller, Olivia DeJonge, Ed Oxenbould, Dacre Montgomery, Aleks Mikic, Patrick Warburton, Virginia Madsen.