Releasing his lowest-grossing film since 2006’s The Prestige was probably not on Christopher Nolan’s agenda for 2020, but then nobody has had exactly the year they expected. Since his big, metallic sci-fi thriller Tenet finally hit cinemas in late August – after months of delay and deliberation – its box-office figures have been the subject of as much variable debate as its tangled, time-slipping plot.

After six weeks of global release, Tenet has grossed more than £235m worldwide – a number that means different things to different analysts. For a latter-day Nolan film, it’s borderline disastrous: far short of the £405m grossed by his last film, Dunkirk, which itself was a modest performer compared to the £830m racked up by The Dark Knight Rises. With a production budget around £154m, it’s fair to say these are not the receipts of Nolan’s or Warner Bros executives’ dreams. Others would argue that they’re not half bad for a film released in the midst of a global pandemic in which the filmgoing public has been actively discouraged from communal indoor activity – a metric for which there is no precedent to set the bar. Globally, it’s the third-highest grosser of the year, behind Chinese epic The Eight Hundred and January’s Bad Boys for Life, which already feels like a relic from another era.

All in all, things could be worse for Tenet – except for the fact that, by just about anyone’s yardstick, things haven’t been nearly good enough. As other summer blockbusters fell off the schedule, delayed to the winter or beyond, Tenet doggedly stuck to its season, even as its opening date crept back from mid-July. Warner Bros was determined that it would be the tentpole event to signify a return to business as usual, even if that meant putting their head above the parapet. That positioning, paired with Nolan’s longstanding reputation as the Hollywood’s pre-eminent stickler for old-school film form – he is as opposed to digital releases as he is to digital cinematography – led to Tenet unenviably being branded as some kind of saviour of cinema.

As it turned out, it was more of a sacrificial lamb. Not exactly compelled by a distinctly mixed bag of reviews – the Guardian’s own critics gave it two-star and five-star write-ups – audiences came out only in the most tentative of droves. If returning to the multiplexes still seemed a bit of a risk in late summer, Warner Bros was hoping crowds would be emboldened in the coming weeks by others’ experience. But as the days passed and the box office total crept up by steady, unexcitable degrees, it was clear that word of mouth wasn’t exactly taking off.

Was the general public simply not ready to go to the movies? Or was Tenet specifically not the film to lure them back? Nolan’s film offers bombastic spectacle, expensively steely fantasy and a handful of supremely good-looking stars in great tailoring: for this critic, at least, that was enough to make it a rollicking good time in a year distinctly short on rollicking. But others were disappointed: widespread complaints hit the internet that it was too long, too cold, too convoluted, too much work to watch at a time when people were after easier comfort viewing. That perception was confirmed in the US by the film’s CinemaScore, an all-important public rating that the major studios regard more anxiously than any critics’ review: Tenet clocked in with a B, which doesn’t sound too bad on the face of it, but was the lowest for a Nolan film since (those pesky magicians again) The Prestige.

It’s quite possible, then, that Tenet would have been an overhyped underperformer even in a non-Covid summer movie season – just as it’s conceivable that a mass audience free of Covid-era anxieties might have been more receptive to the film’s stylish severity of tone. Either way, it seems that Warner Bros banked on the wrong film to save cinema, and beyond that, we can only get into impossible what-ifs. Many critics described Tenet as Christopher Nolan’s version of a James Bond movie; but what if an actual James Bond movie, the repeatedly postponed No Time to Die, had instead been the first to rechristen the dormant multiplexes in August? As a franchise entry, it was always the safer financial bet: perhaps it (or Black Widow, or Wonder Woman 1984, or another known property) could have made the required splash with crowds. We’ll never know.

Whether Tenet was just a victim of timing or a disappointment on its own terms, its fate has thoroughly spooked the industry: no studio is ready to risk offering up one of its prize properties as a safer bet. And so the late-2020 release calendar has emptied, as studios now pin their hopes on next spring being cinema’s comeback season: No Time to Die’s second delay from November to April 2021, a full year after its originally scheduled release, is the clearest example yet of the Tenet effect. (That Disney has drop-kicked Black Widow and West Side Story into 2021, meanwhile, suggests that their experimental tactic of releasing Mulan as a VOD add-on to Disney+ subscribers did not yield the desired returns.)

And yet time is not an infinite resource. Declaring spring the new start of cinemagoing is all well and good, but this week’s shock announcement of Cineworld indefinitely shuttering its cinemas in the UK and US has raised concerns that by the time the studios are ready to release their movies, they may have nowhere for them to play. Tenet didn’t save cinema, that’s for sure – but there’s reason to fear that, by cruel chance, Nolan’s film called time on his beloved medium instead.