Chris Kendall, a former CPR instructor, battled for 15 minutes to save the life of heart attack victim Allan Hainey but was later told by police he had passed away.
So 32-year-old Chris could barely believe his eyes when five months later he got a text from Allan thanking him for helping to save his life.
A grateful Allan, from Wishaw, North Lanarkshire, has invited Chris to be a guest at his 60th birthday this year - a milestone the firefighter helped him reach.
And both men are campaigning for more members of the public to learn CPR.
Chris, from Kent, was driving on the A1 in the Scottish Borders in June this year when he spotted Allan being dragged from his car.
Allan had suffered a myocardial infarction so severe that it blew three holes in his heart.
Chris, who was living in Kincardine, Fife, at the time, gave chest compressions to Allan for 15 minutes - to the tempo of Staying Alive by the Bee Gees.
A mix-up meant that when Chris later asked police about the outcome, he was told that the motorist had died.
Unknown to him, Chris’s CPR had helped keep Allan alive. The Police Scotland IT worker spent 52 days in hospital recovering and having a pacemaker fitted.
And as soon as he was well enough, around the middle of November, Allan got hold of Chris’s mobile number and texted: “Hi Chris, my name is Allan Hainey.
“On the evening of Sunday 25th June this year I had ‘a bit’ of a heart episode near the A1 and Cove village.
“You stopped, assisted and by all accounts from the doctors and surgeons at Edinburgh Infirmary, saved my life.
“My wife, family and myself will be forever grateful. I went through a bit in the hospital, but I’m out and about and doing very well.”
Chris, a fire brigade operational training manager, said getting the text was “the best news ever”.
He said: “I thought he was dead, I was informed by the police that he had passed.
“So, I couldn’t stop smiling when I got his message. I was so excited, because you never really know if you’ve done it properly.
“I was jumping up and down. I couldn’t be happier that he’s alive.”
Chris added: “I would urge everyone to go and undertake formal training. You can walk into any fire station and with the help of a DVD and a dummy you walk out knowing how to do CPR.”
Allan said: “If it wasn’t for Chris I wouldn’t have made it. The doctors and paramedics all said that to me.
“I died twice in the ambulance on the way to hospital in Edinburgh and without Chris resuscitating me I was told my chances of survival were 0%.
“I had such a major myocardial infarction that it blew three holes in my heart.
“I was dying and Chris got to me and brought me back. I am very grateful.”
Allan is now arranging for around 900 colleagues at his workplace to learn how to do CPR.
David McGown, Assistant Chief Officer in the Scottish Fire and Rescue Service, said: “Performing immediate CPR can keep oxygen circulating around the body until medical professionals arrive, and it only takes about half-an-hour to learn the technique.
“Firefighters are available to teach these life-saving skills to communities through schools, local groups and classes.
“This innovative partnership with the British Heart Foundation has equipped all 356 of Scotland’s fire stations with Call Push Rescue training kits.
“Anyone can drop into one of these fire stations and learn CPR.”