In Carmen Nasr's debut play, Dubai sometimes seems like a mirage: this shimmering, glass metropolis, rising out of the desert and glinting in the sun. Like any oasis, it pulls people in. Brash young Brits out to make a buck soak up its luxurious expat lifestyle. Migrant labourers, mostly from the subcontinent, come to work in construction. Journalists seek out their scoops. Dubailand sits them all side by side. It paints a grim picture of globalisation, caught between horror and realism.

"I'm living in the future," says Indian labourer Amar (Adi Chugh), high up at work. He's given up his passport to come here, a downpayment on the wages he's sending home to his family. The expat estate agent Brits might be living in the past, living it up like latterday colonials on a permanent gap-yah. Sloane ranger Jamie (Nicholas Banks) is so oblivious to the situation that he proposes a live-feed of construction to make property dreams seem more concrete. He's forgetting the falls – so commonplace Amar and his colleagues talk of them in casual shorthand over lunch: "How many? What floor?"

It's only when his journalist friend Clara (Miztli Rose Neville) turns up that the scales fall from his eyes, and her probing reveals some unpalatable truths; not least when Amar waves to the camera and steps out into the sky.

Absolutely a play for today, Dubailand is rare in its ability to condense globalisation into drama. Nasr has found its nexus: a gold-rush in the Middle East, essentially. Old economic powers swoop down like vultures, snatching at a new market, while those from poor countries swarm in to exploit opportunity and be exploited. Some lounge around at boozy all-day brunches; others pick at poorly cooked potatoes on tight breaks.

Not only does Nasr paint a chilling picture of a new Wild West – a world in which rich locals hang immigrant taxi drivers by their ties in the desert for the slightest dissent - Nasr grasps all the moral complexity of the whole ecology. Though her play protests against exploitation, her characters make strong cases that can't be shrugged off so simply. Everyone's here for a better life. Cramped accommodation, low wages and poor regulation are more than migrants would manage at home. They're supporting their children in a way that the young Brits have been sold short at home, priced out of their own country.

That Amar takes his life out of guilt, having betrayed a co-worker, deals a sharp sideswipe at bleeding heart liberalism. Our collective guilt, in the west, is greater, no matter how many crocodile tears we shed, and, as Dubailand makes clear, we're just as vulnerable to debt and exploitation. Banks grows in stature as Jamie's dimness settles into seriousness and, eventually, panic.

Dubailand lands one startling and sharp thought in particular. When inequality's this extreme, it stratifies. No-one can climb out of their lot and, in the end, free market capitalism morphs into feudalism, and feudalism into fascism. Orders from on high have to be followed – cars must be sand-free, for example – and, worse, life becomes expendable. Like Dubai, the entire world order seems built on sand, nothing more than a mirage.

The play would benefit from translating that into form, using theatricality to represent Dubai's hyper-reality as Mia Chung's You For Me For You did with North Korea. As it is, a plot centered on an investigative journalist is somewhat see-through, and Georgie Straight's make-do staging can't hide the fact that the writing wears its research too openly, but overlook that and this is proper political theatre: astute, informative and grown-up.

Dubailand runs Sundays and Mondays at the Finborough Theatre until 21 February.