Had it not been for 'three simple words' - the Darwins may have got away with their diabolical scheme.
Conman John Darwin paddled out to sea in his canoe to fake his own death back in 2002, leaving Anne Darwin to play the grieving widow while she collected her husband's £250,000 life insurance policy.
The former couple used their ill-gotten gains to fly around the world in a bid to start a new life, eventually purchasing a £200,000 tropical estate in a village in Panama in 2007.
But John decided to return to the UK after a change in Panama's visa laws, but continued spinning lies by claiming he was suffering from amnesia when he rocked up at a police station.
Initially his remarkable return was hailed as a miracle, but the couple's lies started to unravel when a single photograph exposed their audacious plot.
It may never have been found were it not for a curious young single mum and an efficient estate agent's wife.
While trying to look for somewhere to start their new lives, John and Anne travelled to Panama and started speaking to Mario Vilar, president and managing director of a relocation and land agent company, MoveToPanama.com.
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The company, owned and operated by Mario and his wife Karina, specialised in relocation services and John felt it was an ideal place to seek information about the country he felt sure would offer them a safe haven.
At the end of their trip, Mario asked if he could have his photograph taken with his new British pals - and they didn't put up any resistance.
Former Mirror journalist David Leigh, who was despatched to Panama and managed to track Anne down, explains all in his book The Thief, His Wife and the Canoe on which the ITV drama is based.
"The Darwins had little time to think or make an excuse. Anne gave a big toothy grin as she stood between John and Mario," wrote David.
"They were both conscious that keeping a low profile was imperative, but nevertheless agreed to the photograph. After walking out of Mario’s office, they didn’t give it another thought. What harm could possibly come of it?
"Little could they have imagined how badly that seemingly innocent holiday snap would come back to haunt them seventeen months later."
A police financial investigation had already begun three months before John reappeared as they had suspicions about Anne, who was taking foreign holidays and transferring large sums abroad.
But they got the confirmation they needed when The Mirror published the incriminating snap along with the the headline 'Canoe's this in Panama?'.
The photograph had been found simply by searching for the words 'John', 'Anne' and 'Panama' in Google Images.
Mario's wife, Karina, explained that she was the one responsible for getting the Darwins to pose for the incriminating snap.
David believes wannabe ladies man John wanted to impress the "tall, blonde and vivacious" Karina, while also thinking he would arouse suspicions by saying 'no' to a picture.
"They said that was fine," smiled Karina, "and I took the picture."
Their fate was literally sealed in a flash, with Karina adding that they "might not have mentioned" to the couple that the photo would go online.
Karina made two simple decisions which would incriminate the couple, the first being that she set the camera to burn the date onto the image as it was taken, 18 months before he 'came back from the dead'
Then she typed the words ‘John’ ‘Anne’ and ‘Panama’ and stored them with the website’s address, which meant they could be found in a Google search.
But it wasn't the police that rumbled the photo, as a young, single mother had down her own sleuthing online and rang in.
"She had then used the wonders of the worldwide web to blow John and Anne Darwins' story to smithereens. It was simple but brilliant," wrote David.
"While researching the story online, she entered the words ‘John, Anne and Panama’ into Google and hit ‘images’.
"She pressed the return key and, in the blink of an eye, up popped the astonishing picture. Its existence has exploded the story into a whole new level of drama."
When confronted with the picture, Anne broke down as she told reporters her life had become a "nightmare" and confessed: "Yes, that's him. My sons will never forgive me."
John was sentenced to six years and three months in prison for admitting deception by faking his own death, while Anne received six-and-a-half years behind bars for fraud - with both serving half their sentences.
David explained that Anne often says she "doesn’t understand what all the fuss is about", asking why there is still "all this interest" in the story.
Speaking on This Morning this week, he said: "She obviously wishes this wasn’t happening but accepts she played a role in it and understands, to a degree, the fascination from the public.
"This story has been running now for 15 years and on it goes, so I think she’ll be happy when it’s over and she can get on with her life and spend time with the boys."
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