Nina is a rescue dog, a lurcher, from Battersea Dogs Home. She arrived in 2013, skinny and nervous. I walked her twice a day, unless work got really busy, in which case she’d go out with a dog-walker. On the day she was stolen, 12 July 2016, the dog-walker picked Nina up as usual, put her in the back of the van and carried on her rounds, collecting the other dogs. When she came out of the last house, she saw the van being driven off at speed down the street.

Angela, the owner of the dog-walking company, called to tell me what had happened. We were all in shock. Had they just wanted the van? Would they dump the four dogs? I thought Nina would be back within a few hours. She’d run off before, on holiday, and managed to find her way back, so I knew she was clever. I slept on the sofa night after night with the windows open, hoping to hear her bark.

The police gave us a crime number and ran a search on the number plate, but nothing came up. The organisation DogLost was amazing: volunteers put up hundreds of posters all over the country. They said lost dogs tend to go to ground during the day, so we started looking in the early morning and late evening. They suggested barbecuing sausages outside parks and cemeteries, because the smell would lure any hungry dogs. All we attracted were foxes and odd looks.

For about three months, there was no sign of Nina; possible sightings turned out not to be her, plus there were a few hoax calls and heavy breathers. Then, in October, an anonymous tip came via Facebook. This time, there was no question it was Nina: there was a picture of her in a field next to a guy holding up a dead hare. She’d been used for hunting. It was shocking to think, “My dog’s killed a hare”; but at the same time I now knew she was alive.

We had the man’s name and Facebook account, and Angela and I spent hours online working out where he lived, who his friends and family were. I felt like a stalker. Then, in November, we found another photo of Nina on a different account: a dog dealer was advertising her for sale. She looked terribly skinny and her eyes were a mess. Until then, I’d been holding back so as not to scare anyone off, and the police had warned me about getting directly involved, but seeing that picture was heartbreaking. I had to do something.

I sent the dealer a message using a fake profile: “I think you’ve got my dog.” I was careful not to accuse him. He replied, saying she’d been sold. I offered £300, but he said the new owner was reluctant to sell. We went back and forth until he texted to say she was mine for £1,000, so long as I could meet him in an hour at a service station off the M25.

My partner and I raced around getting the cash together. It stuck in my throat to pay that much money, but I would have given anything to get Nina back. On the way there, I was so anxious: what if it wasn’t her? What if they snatched the money and ran?

The dealer met us and told us to wait in our car until the new owners arrived. We spotted their transit van. I couldn’t bear to look. I heard my partner say, “It’s definitely her.” I opened the boot to get her lead and suddenly Nina broke free from the dealer and leaped into my car. I got in next to her, sobbing with joy and sadness.

She was skeletal; she smelled awful, and her ears and eyes were a mess. She looked at me and wagged her tail a couple of times, then began shaking. Her eyes glazed over. I offered her some cheese, her favourite treat. Gradually, she moved towards me, then crawled into my lap and pushed her head inside my coat. I felt her get heavier as she relaxed.

Of the four dogs that were stolen, three are now back with their owners; we are still searching for Mattie, a yorkshire terrier. The dog-walker’s van was never found.

For a while after we got her back, Nina would stand by the front door when it got dark, waiting to go hunting. She has regained the 3kg she lost, and her scabies and fleas are gone. I’m far more protective now. I’d never leave Nina in the car again or tie her up outside a shop, not even for a minute.

• As told to Rosie Ifould

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