(Spoilers ahead: It would be impossible to write about this film without spoilers so I won’t even try.)

Arrival, the French Canadian director Dennis Villeneuve’s followup to the excellent Sicario, is based on a compelling premise. If we ever make contact with aliens what language would they speak? The problem for me was no so much in its execution as in the way it tries to be two movies in one. On one hand, it’s a fascinating intellectual exercise on the difficulties of communicating with beings we’ve never even imagined existed. On the other hand, it’s a personal story about a woman who loses her child. The mystery that Villenueve so skillfully evokes in the first half of Arrival does not so much get solved as it gets progressively replaced by another narrative altogether. Needless to say, you don’t come out of Arrival knowing whether or not humans will ever be able to talk to aliens. Whether you come out caring about Amy Adams, Jeremy Renner, and their teenage daughter, I will leave for you to decide for yourself.

Amy Adams plays Louise Banks, a professor of linguistics, and the mother of a teenage daughter who we see in what we believe to be flashbacks dying of cancer. They’re not flashbacks but first things first. One day she goes to class, and finds that only a tiny fraction of her students bothered to show up. As she begins a lecture about why Portuguese is so different from French, Spanish, or Italian – I don’t know if it’s true or not but the idea seemed interesting – she realizes that nobody’s paying attention. She stops. What’s going on? I suppose Professor Banks doesn’t look at her iPhone before she gets in her car. In any event, she stops the lecture, and switches her laptop to a news channel. Twelve gigantic alien spaceships have touched down in various place all over the world. Nobody knows who they are or why they’ve come, but the effect has been similar to a hurricane, or perhaps more accurate, a blackout. Society is breaking down. People are panicking, rioting, looting.

The mystery of why a college professor like Louise Banks has such a fine house on the lake is immediately cleared up when she goes home to find G T Weber, a United States Army Colonel played by Forrest Whitaker. Banks is not only a college teacher. She’s a world-renowned expert on the short list of consultants the military turns to for advice in the event of an alien invasion. After the army takes her by helicopter to the site of one of the alien ships in Montana, she meets Ian Donnelly, a theoretical physicist played by Jeremy Renner who’s also on the army’s short list of go to consultants, and a man with whom she establishes an immediate emotional bond. Have they met before? We think about Louise Banks’ flashbacks to the death of her daughter, first a little girl, then a teenager who with a shaved head dying of cancer. We wonder what her husband was like. We never see him in the flashbacks. We wonder if she’ll ever get married again. We weigh in our minds about whether or not she’d be compatible with Ian Donnelly and decide that yes, she probably will.

Imagining what aliens look like is the most difficult job for a filmmaker. The easiest way to get around the problem is simply to imagine either that the aliens take on some sort of “human form” or that they’re simply humanoids from another planet. In the classic 1951 film The Day the Earth Stood Still, to which arrival owes some of its pacifist subtext, the alien Klatu is simply a man in a what looks to be a silver tracksuit. In the 1980s gothic, science fiction horror film Alien the alien is a terrifying, bug-like monster. In the 1984 movie Starman, he’s Jeff Bridges. Dennis Villeneuve chooses to imagine his aliens not as humanoid, but instead as gigantic, technically advanced jelly fishes. Even though they don’t make any aggressive moves, they look terrifying, and when Louise Banks and Ian Donnelly put on Hazmat suits and enter the alien ships, we fear for their lives, even though we know they’re not in any real danger. Donnelly and Banks, however, and especially Banks, have none of the usual fear of the “other.” Banks even removes her helmet and walks up to the clear barrier the aliens have erected between themselves and their human hosts. Back at her house on the lake, Colonel Weber had played her a tape of what the aliens sounded like, but she’s got a better idea. When one of the aliens sprays the clear barrier with what appears to be a type of ink, we understand what she meant. Language isn’t aural. Language is visual.

While Louise Banks or Ian Donnelly may not have a visceral fear of the “other,” they are highly educated, elite intellectuals. The rest of the world, especially the military, and most especially General Shang of the Peoples Liberation Army of China, are beginning to get paranoid. When the Chinese army mistranslated the word “gift” or “tool” as “weapon,” Arrival becomes a race against time. As Banks and Donnelly are working to decipher the series of images the aliens spray onto the barrier, China, then Russia, then Pakistan, then every landing site on earth cuts itself off from the United States, and prepare to follow the lead of Shang, who has delivered an ultimatum to the ship near Shanghai. Leave Chinese territory or be destroyed. Even rogue troops in Colonel Weber’s garrison in Montana plant a bomb, and try to kill Banks and Donelly in order to sabotage their growing rapport with the aliens. Eventually, however, Banks’ tenacity and courage and Donnelly’s scientific training and ability to think in mathematical abstractions pay off, and Banks cracks the alien code. By this time, we know that mankind is on the verge, not of annihilation, but of a series of discoveries about space, and about ourselves, and we root for the two scientists to prevent the coming attack. Destroying the twelve alien ships would be akin to smashing the Rosetta Stone or burning down the ancient library at Alexandria.

Oddly enough, it’s at this moment that the movie begins to fall apart. If you’re familiar with the history of cinema and science fiction, you’ve already figured out by this time that Arrival is a plea for world peace and international cooperation, The Day the Earth Stood Still with aliens that look like squids and not humans. The problem isn’t the message so much as it’s the lack of historical context. That the original short story was written a by Chinese writer doesn’t change the way General Shang is cast as the paranoid war monger and Louise Banks as the enlightened white savior. Indeed, the clumsy attempt by Colonel Weber’s rogue soldiers to bomb the alien space is confusing, slows down the narrative, and was obviously Villeneuve’s way of hedging himself against accusations of Sinophobia and Orientalism. That there’s a more complex narrative twist underneath the plea for internationalism should theoretically deepen the film’s mystery. Stop reading now if you haven’t seen the film. Banks’ mastery of the alien language also means an understanding of their non-linear conception of time. She can now look into the future. Not only does her newfound understanding of time allow Louise Brooks to make a satellite phone call to General Chang and talk him out of starting a war with the aliens, we realize that the father of her dying teenage daughter is none other than Ian Donnelly, that what we thought were flashbacks were actually flash-forwards.

If all this sounds great to you, then by all means go see Arrival. You may like it more than I did. Theoretically it’s a clever resolution, a neat little narrative trick that lets Dennis Villeneuve wrap up the story with a neat little bow. It certainly does “make you think,” but to me it not only felt unfinished – exactly how Louise Banks managed to talk General Shang out of starting the war is never made entirely clear – it felt a bit like a bait and switch. Amy Adams and Jeremy Renner are both likable actors I’ve enjoyed in previous movies, but their relationship never feels strong enough to carry such a radical shift in the plot. The idea of a teenage girl dying of cancer is as sad a story as you can imagine, but we never really get to know “Hannah”–the name is supposed to have some significance to the movie’s non-linear conception of time because it’s spelled the same backwards as it is forwards–well enough to care about her as an individual. The utterly fascinating exploration of “the other,” and the baffling mystery of learning not only a foreign language, but an extraterrestrial language, has given way to a domestic tragedy. Louise decides to give birth even though she knows her child will die young. Ian blames her for making the wrong decision and leaves her. Villeneuve has succeeded, not so much in resolving or in further exploring the film’s great premise so much as in sidestepping the admittedly impossible mystery and finessing us into another film altogether. It’s not that we don’t admire his cleverness. We just wish he had explored Arrival’s more abstract and intellectual premise in more detail, and saved the familiar romantic drama for another movie.