Mr Smith goes to . . . The Crypt

They've been bringing out bodies at a rate of more than a hundred a week. The corpses have been there for so long that you are not allowed near them until a doctor has passed you fit. "The Doc's one of the top people with the Home Office," says a workman at the site. "Lovely old girl, but a bit strict." The Doc has brought home-made cakes for the workers this morning. In her spectacles and tweed skirt, she might be the science mistress at a boarding school. "Let's have a look at your arm," she instructs me. It's a suitably bone-cold day, but I gingerly take off my jumper and the Doc detects the puncture mark, the botched skin-graft of a scar, which confirms that I've been inoculated against smallpox. Now there are no excuses for avoiding a trip into the crypt. Unsuspecting City workers carrying their bagged breakfasts pass within a few feet of its mouth, where a conveyor belt churns soil and brick to the surface behind a canopy of tarpaulins.

The tomb filled with debris after the church that stands on top of it was bombed during the Blitz. The burial chamber has been exporting damp to the rest of the premises, so the Anglican hierarchy has given permission for the bodies to be removed and reinterred elsewhere. The excellent cadavers are thought to include Sir Edward Coke, attorney general to Elizabeth I, and Daniel Purcell, brother of the famous composer. The sextons are running a sweepstake on how many remains they'll find. The makeshift book is displayed on the wall of a Portakabin; the estimates begin among the substantial four figures.

Fantastically buckled, the lead caskets protrude from the spoils like an installation by Salvador DalI in one of his less playful moods. Other casings have crumbled altogether, into flakes the consistency and colour of ash bark. An archaeologist has just brushed away the dirt from the smoothest of pates, the skull as brown as a mug of tea because of the pigments released by the rotting coffin timber.

Although this is a charnel house, the experience doesn't make your gorge rise as much as you might expect. For one thing, there is no overpowering smell, only the chalky odour of earth. For another, the contract is in the horny but tender hands of the Toop family, a father-and-son concern from south London. After many years as subcontractors in the undertaking and exhuming game, the Dickensian-monikered Toops are in business for themselves, competing in a sector now not much different from any other, they say, with its emphasis on the bottom line.

But the Toops are Catholics, their daily contact with death not leaving them blase in the face of it, but reinforcing their faith. Pat Toop, who is 68, tells me about a commission to "lift" two dozen nuns from a rural convent. "I had a priest to bless my men every day," he says. Every day? Toop rounds on me in the gloom. "Would you want to lift 22 brides of Christ without being blessed?"

Under the screen of tarpaulins is an unmarked van. Every morning at seven o'clock, it leaves for the City of London cemetery in Ilford. Pat's son, Mark Toop, sees it off, sombrely doffing his hard hat.