Karen Fox and Dan Hewko of Havelock North are appealing to a stranger who took their pet pooch to return the dog.
They have launched a search in the hope of finding Molly, their 10-year old tricolour beagle.
Ms Fox said Mr Hewko was walking their two beagle dogs, 10-year-old sisters Molly and Katie, along the pathway near the Tukituki River on Tuesday.
"Molly touched an electric fence and got spooked," Ms Fox said. "She ran off into the thick brush and disappeared almost immediately. Dan spent the rest of the day walking up and down looking for her."
Both dogs had their owners' phone numbers printed on their collars.
"When I got home from work at 3pm there was a message on the answering machine from a council employee called Steven who said he had our dog."
It appeared Molly had made her own way back to her owner's car when she was initially spotted by Steven.
But before Molly could be returned home, the dog was handed to another man who said he would be able to take the pet to its owners.
"Steven gave Molly to a man called Larry who said he had a friend who had a car and they would be able to take her home but never did," Ms Fox said.
Steven had managed to get a phone number for Larry but attempts to contact him had been unsuccessful. "You ring the number and it just goes to answerphone," Ms Fox said.
Yesterday Mr Hewko was again searching the Blackbridge area and putting up posters of Molly in the hope someone had seen the dog and would be able to help with her return. Ms Fox had passed on the poster to vet clinics in case staff and customers had seen Molly.
Ms Fox said she was "worried sick" and as well, Katie had begun to fret for her sister.
"Katie won't move and she won't eat. She wants her sister back. They were like two peas in a pod. We've had them both for 10 years. We brought them out here when we moved over from the States."
Constable Alan Daly of Clive Police said he had tried to call the man who gave his name as "Larry" but had had no response. "This chap had been down by Blackbridge in the carpark and had spoken to a number of people. He was on a moped-type motorbike, which was a blue colour. He was a man of a thin build probably in his mid-20s. He could face charges if he doesn't return the dog."
Mr Daly said people could contact him at the Clive Police Station if they had information to help find Molly.