Ooh, you called my bluff when I didn't have any rat gossip to share.
Er - did anyone else read Rattus Rex as a kid? Like Talons of Weng-Chiang, it starts with the giant rat of Sumatra mentioned by Sherlock Holmes, and goes down into the sewers, but then off in another direction entirely.
There's almost nothing about it online, except that one reason why everyone except me has forgotten about it is that James Herbert came along with The Rats shortly afterwards.
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' "Haven't got houses." Where do they live then?'