I was doing some Christmas shopping today and in a dusty old curiosity shop in a London backstreet I found a beautifully-made ornamental brass rat. It was only a tenner, which was very cheap for such a well-crafted ornament, and I thought it would be perfect for my mad uncle who collects ornamental rats so I decided to buy it.

The proprietor of the shop said that although the rat itself was only a tenner it would cost me fifty quid if I wanted the story to go with it. This seemed a bit steep, even more of a daylight robbery than a Currys extended warranty agreement, so I declined the offer of the story and just took the rat. No story could be worth forty pounds.

As I was walking back towards the office I heard a noise behind me, turned and saw a rat following me down the street. I started to walk a little faster. At every corner, other rats came out of drains and through gaps in hoardings until I had a huge pack of rats following me.

By now I was practically running and causing quite a scene as I had reached busier streets and the lunchtime crowds were parting in front of me as son as they saw the mass of furry bodies chasing me. And all the while the pack was increasing in number.

Having read all of James Herbert's books I was getting more than a little worried by now and I headed for the Southbank. I thought that if I went up the stairs to the Jubilee bridge they rats would not be able to follow, but follow they did: no trouble with the gaps between the stairs at all.

I was halfway across the river when the rats had almost caught up with me and, fearing for my life, I threw the brass rat over the side into the river. It was a desperate measure and I don't know why I did it, but all the rats then ignored me and launched themselves into the Thames after the ornament.

Phew!

I returned to the shop later. The shop-keeper looked smug and said, "I knew you would be back! You'll be wanting to hear the story now I suppose?"

"Actually, you can keep the story." I said, "I was just wondering if you had any ornamental brass conservatives I could buy."