What a difference a decade makes. Titas Halder's second play flashes back and forward across ten years. Three flatmates toasting the end of their student years grow into anxious adults in a world gone wrong. Their student digs look the same as ever. Nothing else is as it was – or, indeed, as it was meant to be.

Coming only a month after his debut Run the Beast Down, Escape the Scaffold is almost Frankensteinian in form. It's as if two plays have been stitched together: a domestic drama wakes up to find it's become a dystopian thriller. It's a witty formal disruption – a mark of the way the world refuses to run in neat narrative arcs – that encapsulates a decade gone altogether awry. Imagine The Walking Dead were a sequel to This Life and, rather than running his own legal team, Egg found himself fighting off zombies.

Ten years after graduating, Grace (Rosie Sheehy) and Marcus (Charles Reston) have bought out their old student flat – a move sodden with nostalgia that speaks volumes about their relationship and the world outside. It's a retreat and a regression. It's still stained glass and original floorboards, only now it's in a gated community – student stock become prime real estate – and, rather ominously, the cellar's flooded. The door's locked. The world is different. Meat comes off the black market, most of it rancid. Helicopters circle overhead.

Halder flashes back to happier times – to student Sunday roasts with cheap red wine. Optimism rules. Marcus has cooked his first chicken and, inevitably, forgotten the gravy. He's also bought a ring. And a lot of tequila. Grace, unawares, giggles and giggles. Her eyes dart across the table to Aaron (Trieve Blackwood-Cambridge).

Escape the Scaffold hones in on the potential of that moment. Essentially, Grace faces a choice: stability with Marcus, steadfast old Etonian prat, all grad schemes and getting ahead, or something less predictable, more passionate with artistic Aaron. His return, on the run ten years later, throws up a lot of old feelings and resentments. Halder drops more than a passing nod to Harold Pinter's Old Times.

Anyone who graduated ahead of the credit crunch will recognise their lot in that. The hopes of those halcyon days, when Tony 'Education' Blair told us anything was possible, have been ground down into despair and, as Brexit looms, disaster. The realists have gotten away with it, especially if, like Marcus, they once called Eton home. Dreamers and radicals like Grace and Aaron haven't. Beneath the dry humour and the lick of spoof in Halder's play, there's a palpable sense of anger.

In truth, his student dinner is far sharper than his spy drama, and he catches the buoyancy and freedom of undergraduate life beautifully. There's a sense that anything is possible in these three. Sheehy, in particular, displays a gorgeous ease that all but evaporates as she ages. Reston's bluster loses its charm. His silver spoon charm twists into a sneer.

Nonetheless, the play overstretches itself and Hannah Price's production strains for credibility. It's possible to illustrate establishment thinking without setting a government spy against Britain's most wanted – both of whom happen to have shared student digs as rivals in love. Restraint would have saved a brilliant idea, but Halder's writing gets stuck in fast-forward trying to cram everything in and, by the point Grace and Aaron really round on Marcus, a mark of a white, male elite in crisis, it's clear the scheme is leading the story.

Escape the Scaffold runs at Theatre503 until 15 April, then transfers to the Other Room in Cardiff, 19 April to 6 May.