With Birdman and The Revenant, Alejandro G Iñárritu is the only living filmmaker to have won the Oscar for Best Director two years in a row. He’s also the only artist, it seems, with the clout and audacity to make Digger, an aggressively strange, expensive, star-studded film that’s hard to explain if you’ve only seen the trailer. Somehow, though, Digger is even trickier to put into words when you’ve watched the entire film twice like I have. It’s a political satire starring Tom Cruise in prosthetics as a cartoonish oil tycoon called Digger Rockwell. It also very much isn’t.

Perhaps it’s best to remember, then, Iñárritu’s 2000 debut feature, Amores Perros, a dark, disturbing drama that, 40 minutes into its run time, momentarily switches to a buoyant montage set to the hip-hop song “Si Señor”. Digger, a tragedy dressed up as a comedy, does the reverse. For the first half hour, Cruise’s line delivery is overly snappy, the production design is suspiciously meticulous, and there’s even a meowing puppet cat for comic relief. The tone then completely changes, revealing the film to be entirely different from what’s advertised. (Imagine a poster for The Revenant with Leo relishing a scenic boat ride.) This twist isn’t in the trailer, and Iñárritu himself requests for it to not be revealed in any coverage.

I’m speaking to Iñárritu in London, in late September, the morning after the film’s world premiere. “I will never watch Digger the way you did,” he says, referring to the story’s surprises. “I would have loved to have discovered the film as you did.” After observing Bardo with a crowd at Venice, the 63-year-old Mexican director cut 15 minutes from the version that ended up on Netflix. “Seeing a film with a real audience, it reveals itself to you,” he says. “Sometimes I have doubts. But yesterday I felt serene. I wasn’t struggling, thinking, ‘This is too slow,’ or, ‘I should have kept that scene.’ It was a pleasant experience, strangely for me.”

The film itself is far from serene. Outdoing the intensity of his motivational speaker character in Magnolia (and also the leaked clip of him getting angry at unmasked colleagues during a Mission: Impossible shoot during COVID), Cruise ferociously spits spiky dialogue about oil, his family’s Texan roots and his value to America. His rants are matched by his manic sister (Sandra Hüller), the misogynistic US President (John Goodman), and a scientist, Ganesh (Riz Ahmed), who makes a discovery: Digger’s greed for oil has led to a dislodged ice shelf that, if it isn’t averted, might kill millions.

When the President learns it’ll cost trillions to nuke Judy (their name for the iceberg heading towards Europe), Digger suggests it’ll be cheaper to use “a Firewall” – an AI-assisted tool that removes key words like “global warming” and “Al Gore” from social media and news stories. Iñárritu and Sabina Berman wrote the first draft in 2017. “At that time, Sabina and I thought the Firewall was a crazy idea, and now it exists. Everything Ganesh says is the truth and science-based. I worked with two different scientists, and travelled twice to the Arctic. They told me in 30 years we have a window to react. At that time, there had never been a detached ice shelf. Greenland wasn’t on the map of the United States. And now it is. We were ahead by ten years, and unfortunately that’s where we’re heading.”

If there’s the equivalent of the death-defying stunt that everyone remembers from a Mission: Impossible movie, it’s Cruise’s ten-minute monologue on an elaborate, revolving stage to a crowd of faces painted with white makeup. Have Iñárritu, Cruise, and cinematographer Emmanuel “Chivo” Lubezki smuggled a Roy Andersson film into multiplexes? “I love Roy Andersson, and I know him well,” says Iñárritu. “I visit him, and I like his films. But it’s so far from Roy. He hardly moves the camera, and there’s hardly any dialogue. I’m not denying he’s an inspiration – but his inspirations were some of ours.”

Theatre is a way to represent reality, and that representation is sometimes more real than reality because it allows us to see ourselves – and laugh about ourselves

Iñárritu lists examples of painters: Hammershøi and Vermeer for their colours; Hopper and Rembrandt for their approach to contrast. “The faces don’t always have that shadowy thing. It’s mainly painters who use light like that. I used that because this is a film about white men taking power, and controlling the world, and operating on this level almost like ghosts. Chivo and I decided that if Digger is ruling the narrative, the colour is vanishing, and there’s the whiteness of the world we’re living in.”

On the script (Alexander Dinelaris and Nicolás Giacobone joined for later drafts), Iñárritu drew from “self-aware Spanish-speaking literature” like Ernesto Sabato, Julio Cortázar, Miguel de Unamuno and Miguel de Cervantes. He names films he screened to his cast like His Girl Friday (“it’s the timing of the dialogue”), The Firemen’s Ballroom (“because of the madness and absurdity”), and Network (“for that speech”). On walls in the background, posters can be seen for Opening Night and To Be or Not to Be, the latter a 1942 Lubitsch comedy that satirised Hitler during World War 2.

In fact, the film, shot entirely on VistaVision cameras, packs each corner of the frame with thematic clues. While most of the film deals with politicians, millionaires, and extras who may or may not look like they’re from Songs from the Second Floor, it also reveals what life is like for the general public outside Digger’s mansion. An ironic piece of graffiti spraypainted onto concrete in the street says it all: “COMPLIANCE IS FREEDOM”. It suggests that everyone, not just Digger, needs to rethink their part in the world.

I ask Iñárritu about the film’s tonal changes, primarily how the bawdy, slapstick comedy and screwball pratfalls can suddenly switch to drama. “The film’s about storytelling,” he says. “It’s about the stories we tell ourselves, the futility of art, and the importance of art as a way to explain ourselves when we’re dealing with so much reality. Theatre is a way to represent reality, and that representation is sometimes more real than reality because it allows us to see ourselves – and laugh about ourselves.”

He continues: “This film is about your generation. You’re dealing with people taking the narrative and telling you that everything is fine, when you guys know that everything is not fine. You are being bombarded with narratives all day. Powerful people are controlling the narrative for their own interests. You have to decide which story you want to tell yourself.”

Digger is out in UK cinemas on October 2.