If I were you I'd get Rentokil in - there are rats abound in London and if you are serving-up a fine meaty supper for them every night, then you're likely to be a victim.

Check under kitchen units, any gaps (regardless of how small) that might allow the blighters to get from beneath the floorboards into your home. And if in doubt, set some traps - you can get hold of some decent ones from Homebase.

Keith.