As war broke out in September 1939, there was a great panic about the nation's pets and suddenly queues formed outside the vet clinics as people took up to 750,000 domestic animals - mainly cats and dogs - to be put down.
Remember the CJD crisis when cattle were piled up in a field and burnt? Echoes of the Holocaust? Well, that was the scene in some places.
As I researched further it seemed to me that there was a story to be told here. I have a great passion for history and have a nose for untold stories. I just had to choose my audience. If I wrote a novel for adults, it would probably be quite gut grinding with some of the details I was unearthing. I didn't think this would work as a Y.A. novel - they'd all be too worried about falling in and out of love to focus on the animals. This had to be a children's story, I decided, eight years upwards and of course older readers enjoy a good children's story too.
My next question was, What would the children do if their parents told them that just before they are evacuated, their pets would be taken to the vet and put down because - as the government leaflet said - "It's the kindest thing to do?"
Put up the blackout, send the children away and put down your pets. That's how to get ready for the war!
The Grand Union canal goes through Hayes.
It seemed to me that the children would decide not to give up their pets to be murdered and so they would try and spirit them away until they decided how to save them once war broke out. They decide to call their hideout The Emergency Zoo because someone brings a baby cobra from London Zoo.
I was very keen to have a wide a variety of animals as possible in the zoo. There were hundreds of thousands of animals kept in London before the war, including chickens, caged birds and monkeys. I was desperate to fit a monkey into the emergency zoo but I really didn't think the children would be able to manage. Apart from the cobra, I included a bad tempered goat, a parrot with a horrendous beak and a huge boxer dog.
But of course, most of the pets were the lovely, friendly fluffy kind that most children like to keep.
My book The Emergency Zoo comes out in May 2016. I will be visiting schools to give talks and I've decided that I want to take the zoo with me. So under my desk I have gathered a huge bag of toy animals, including a snake, a very endearing white rat and a rabbit which moves. Can't wait!