There is a story about Fritz Lang, that when the German film director first saw the towers of New York, he turned to his companion and exclaimed: “Look! What magnificent ruins they will make!”

This exhibition of coolly dispassionate photographs portrays an un-ruin. The Last Things is fascinating for the access granted to the photographer David Moore as much as the pictures themselves. They show to the world a place very few were intended to ever see; and those who did see it, if things had gone to plan, would see no other place for the rest of their lives.

It looks like a maximum security prison. It has the steel doors and the metallic functionality of, say, the H-Blocks, but without the sweat and grime of, say, Abu Ghraib. It is directly below the streets of central London.

Those trapped in this place may well have asked the dozens of questions that make up Chris Petit’s brilliant introduction to the book of the show. “Will people miss what has been lost? What accommodation is made for nearest and dearest, lovers and children, or is the selection process ruthless? Has Peter Mandelson wangled his way down here somehow?”

What is portrayed in this exhibition is the Ministry of Defence’s Crisis Management facility, to be occupied when the apocalypse unleashes across the rooftops of London and the rest of the Kingdom. This is where the end will be regulated.

There are no people in these snaps, and very little to occupy the corneas. The bare necessities are just enough. A barren TV studio to send messages to the citizenry, or simply to ask, “Is there anybody out there?” The cheap Constablesque landscape print in The Principal Office, the last home for the last Prime Minister. The metal cupboard in the Site Manager’s stores, with dozens of packets of Tesco’s cheapest toothpaste and toothbrushes, and three cartons of Kiwi black shoe polish.

It is all rather poignant and, this side of the Cold War, slightly comic. This is why it is an un-ruin. It is pristine and perfectly usable, but it is a relic from the time when a paranoid gerontocracy in the Kremlin were petrified of a senile oaf called Ronald Reagan who used to make jokes about winning “limited” nuclear wars in Europe. These bunkers were designed to remain when the earth above became a radioactive ruin.

And then, in the space of time that it took this exhibition to open in the Belfast Exposed Gallery, the old fissure opened across the continent and Russia seemed more than the failed empire it had been for two decades. The cool and detached spirit of these photos has been interrupted by a darker context.

Telephones, CCTV cameras, breathing apparatus kits, radiation showers, document shredders, decontamination suites, Len Deighton’s Ipcress File, maps, identity cards, a medical bay triage, the Daily Occurrence Book, mouthwash…

That is the way the world ends, not with a whimper, but a gargle. Or as Petit’s essay concludes: “And will there be a moment when everyone looks at each other and realises: this is it.”

John O’Farrell