Rat Crufts '95 had come to town and pedigree rodents from throughout England vied for the accolade of Best in Show.
According to the National Fancy Rat Society, which organised the show, fancy rats should be refined, affectionate and delicate, and generally as far removed from the sewage-eating variety as possible. Discoloured fur, dirty tails and obesity are out. Points are also awarded for temperament: at one point judge Tina Gruber rubs a competitor against her chin to see how it will react.
Lively teenage does (female rats) are considered the most glamorous; any rat over six months old is considered to be past it. "What we are really trying to produce," confides one owner, "is the rodent equivalent of Kate Moss."
Along with the hard-core rat breeders, all happy to share the minutiae of rodent lifestyles, are (inexplicably) a remarkable number of nurses and care assistants, a few rat-owning families and a host of young women who say they find rodents "cute". In the company of fellow enthusiasts, they become quite animated.
"I've trained my rats to respond to a whistle like a dog," says Geoff Izzard. Another rat-owner confesses that she walks her pets on a harness with balloons attached.
Elizabeth Gough, 26, confides that although she likes her boyfriend's rat, she is disturbed by some of its habits. Once, she says, it shredded her entire T-shirt collection. "Look at that one - it's huge!" she shrieks, spotting an enormous curled-up male. "Picking up that one would really bother me. It has huge balls."
Most of the people at the show own at least seven rats. Optician Stewart Earl has 20, which he keeps in his front room. "It's only a small stud at the moment. I want to build it up and get more," he says. "My friends think I'm quite strange when I mention the rats. But they like them when they meet them."
One man, who only a few years ago bought his first fancy rat at Harrods, now owns over 30. Carol Fisher, whom I found clipping her rodent's toenails with a human manicure set, houses her 86 rats in a converted garage. "A rat is a poor man's racehorse," she says.
Rats of dubious ancestry are looked down on as unsuitable breeding material. It is a dismissable offence for a member of the National Fancy Rat Society to cross-breed wild rats with the domestic variety. And a rat with a mean disposition should never be bred or shown.
Eleven-year-old Charles Green seems unaware of this. His champion buck, Egbert, has just taken a chunk out of his finger.
"It's not like dog breeding," says NFRS secretary Greg Baker. "We show for recognition, not money, and we don't go in for interbreeding to get good results. We're not as bitchy as at other animal shows."
But when Mr Baker's 14-month-old rat comes out of retirement to scuttle away with the Best in Show rosette, murmurs of discontent can still be heard. "I can't believe it," seethes one owner. "My rat's just been beaten by an old age pensioner."