Meet Gentle Ben, the heroic hound who repaid his rescuers by saving their lives from carbon monoxide poisoning.
The collie-husky cross was about to be put down at the dog pound last Saturday when he was rescued by Mallusk couple Sara Tinkler and Stephen Graham.
That night Gentle Ben repaid their kindness by saving them from asphyxiation.
The pair, who run a Facebook rescue dog service called 4 Paws Halfway Home, were planning to hand him over to his new owners the same day, but are thanking their lucky stars that, because of a delay, he stayed the night.
Early on Sunday morning he woke the whole household by barking frantically - and when Stephen went downstairs to investigate he found that a smouldering fire had filled the living room with deadly carbon monoxide gas.
On Saturday night the couple were looking after their own four dogs, plus four rescue dogs that had been due to be put down.
"It breaks our heart to see them put down. We work really hard to rehome them," Sara said.
"On Saturday we had lit the fire about 7pm and we went to bed about 10.30pm. We put the fireguard on and let the fire burn out, as you do.
"But about 2.30am, the collie-husky cross that we had picked up on Saturday woke the whole house up with his barking.
"When my boyfriend went to the door, he heard beeping from the carbon monoxide monitor beside the fire. It was reading 52 - it had always said zero before. So we rang the fire brigade's non-emergency number for advice."
The adviser warned that even low levels of carbon monoxide can kill if it builds up over a number of hours, so Sara and Stephen let all the dogs into the garden and went outside to wait in their pyjamas.
Northern Ireland Fire and Rescue Service said two fire appliances from Glengormley Fire Station were called to the house, after a carbon monoxide alarm had been activated due to a high level reading.
"Two firefighters wearing breathing apparatus entered the house and two occupants were taken from the premises. Both occupants did not receive any injuries during the incident," a spokesman said.
Sara said the fire had burned to ashes and because it was no longer hot, the chimney was unable to draw the poisonous gases out of the room.
"The carbon monoxide was filling the room," she said.
"We were just burning ordinary coal in an open fire.
"We were out of the house for about two hours. Our neighbours were bringing us cups of tea and cake.
"It was a case of Gentle Ben waking us all up and alerting us - he was running about the room barking. We hugged the life out of him and gave him lots of treats."
Now the heroic dog has been rewarded with a fresh lease of life and has gone to a new home just three miles away.
Sara says that the couple have begun fundraising for their work on the 4 Paws Halfway Home Facebook page because they were facing large vet bills for rescue dogs, which are often sick when they arrive with them.
The Northern Ireland Fire and Rescue Service is reminding homeowners with gas or wood burning fireplaces to check for excessive condensation and check all heating a cooking appliances regularly.
For carbon monoxide advice, contact the Health and Safety Executive for Northern Ireland (HSENI) by calling their Carbon Monoxide Advice Line on 0800 0320 121 or by logging onto their website at www.hseni.gov.uk/watchout for information.