Time has worked an odd switch on Stephen King. The recent TV series Stranger Things – a sort of illustrated essay on High Kingiana – tied the man to a period. He began writing in the 1970s. He is still writing effectively today. But that show framed his key tropes in endless 1980s ephemera. He now seems as much a signifier of the Reagan era as leg warmers or Pac-Man.

That conversation continues in this passable, industry-standard take on the first half of King's bullet-stopping 1986 novel It. Out there on social media, there was much smug ridicule of young people (mostly imagined, I suspect) who felt the trailer was influenced by Stranger Things. The fictional whingers weren't all wrong. The feedback loop that binds the book, the 1990 It mini-series, Stranger Things and Andy Muschietti's new film ratchets loudly throughout. I'm sure it's just a coincidence that young Finn Wolfhard stars in both.

This peculiar rearrangement is all the more conspicuous because It was originally divided between the 1950s and the 1980s. The fetishisation of the rock'n'roll era has been replaced by pointed celebration of New Kids on the Block, videogame arcades and faux-neon lettering. If we get to part two, we will, presumably, be back in the undemanding "now".

For the moment, we go among a group of young fellows bonding and fretting in the last years of (oh, why not?) the King Decade. The screenplay hacks the story apart with more ruthlessness than clarity. Over the course of a summer, the boys – and one girl – trade various anxieties to form a self-described Losers Club. Ben (Jeremy Ray Taylor) is overweight and lonely. Eddie (Jack Dylan Grazer) is plagued with incessant hypochondria. Bill (Jaeden Lieberher) frets over the day his young brother, Georgie, went missing.

The opening sequence, detailing the younger boy’s horrific encounter with the infamous Pennywise, trades in an ominous crudity that too accurately presages the broad strokes to come. Rain splatters the windows of a dark house. Georgie’s mum plays the sort of plink-plonk piano music that one only hears at the opening of so-so ghost stories. Chasing his paper boat down a waterlogged gutter, the young boy eventually encounters a pair of mad eyes staring from the storm drain. It is Pennywise the Dancing Clown (a perfectly grand Bill Skarsgård) and, if you’ve read the book, you’ll know he is here to feed on the citizens’ fears and phobias.

Those unfamiliar with the story will have greater trouble working out what the heck is going on. Young actors of various abilities struggle with thumbnail character studies that barely convey even the key anxieties mentioned above. Comparison with the beautiful performances and the sharp writing in Stand By Me does this gang no favours at all. The town's sombre history is rushed through in hurried expository sequences with little dramatic structure. Something awful happened that causes disappearances every now and then. You'll get little more than that from the screenplay.

The escalating horrors are delivered via a rapid fusillade of discrete episodes that suggest journeys in a clunky, analogue-era ghost train. When all else fails, let’s have the mad clown jump loudly from the nearest large box.

For all that, this version of It works on its own degraded terms. Filleting out the grown-up characters' stories – originally woven through the narrative – leaves us with a plain, linear yarn that, despite the planned bifurcation, ends with a satisfactory full stop. The final impression is of middle-ranking Kingiana sold and displayed by the yard. Have some kids on bicycles. Have a little New England gothic. Have some pop-cultural nostalgia.

Such stuff still sells. The film should do well enough to generate another few yards in a year or two’s time.