Animal welfare charity the RSPCA is hoping to find homes for a dozen cats who came into their care from a home where there were 40 moggies.
Most of the cats, which were found in Wembley and brought to RSPCA Middlesex North West branch in June, already have new families but 12 are still looking.
They range from three months old to one year old and have "unique" personalities and "plenty of love to give", the charity said.
According to RSPCA, their previous owner took in two pregnant female cats and as the litters were not neutered over the course of the year the "two cats turned into 40".
Sarah Blackband, animal welfare officer for the branch, said: “Especially in London this is quite a common situation where someone has started off with two cats and things have spiralled out of control.
"It really hits home that it really is important to spay and neuter cats to prevent unwanted pregnancies.”
The charity, which often helps people struggling to cope with numerous animals, explained that cats generally prefer to live independently rather than with other pets.
However, as these cats have formed friendships the charity would like to see them re-homed in pairs.
Mrs Blackband added: “As with many large number multi-cat households a lot of the cats that have come to us are very shy and not used to a lot of one to one attention."
“These cats are quite shy and are going to need lots of patience and care when they find their forever home but each one has made vast improvements since coming to us," she said.
All the cats will need access to a garden and can live with older children.
If you think you can give them a home contact the Middlesex North West branch on 020 8966 9688, or visit the branch find a pet page.
Keep up to date with the latest news in west London via the free getwestlondon app.
You can set up your app to see all the latest news and events from your area, plus receive push notifications for breaking news.