The Secret first aired in 2016, so many will be familiar with James Nesbitt's portrayal of murderer Colin Howell. However, the series has been gaining traction again thanks to it landing on Netflix and many have been hooked by the shocking story.
The drama is based on the double-murder of Lesley Howell and Trevor Buchanan, who were killed in Northern Ireland back in 1991. Many will already know that Colin and his partner, Hazel, were responsible for the deaths of their respective spouses. But where are they now? Here's what we know...
WATCH: Crime thriller The Secret is now on Netflix
Where is Colin Howell now?
As of today Colin Howell, who previously worked a dentist, is still alive and is currently serving a prison sentence for murdering his wife Lesley and Trevor Buchanan in 1991. However, the truth behind their death was not known until 2010 when Colin confessed to the killings.
Colin confessed to a church pastor in 2009, before he was found guilty in 2010. He's currently carrying out his 21-year sentence in Maghaberry Prison in Northern Ireland, with his release thought to be set for 2031.
James Nesbitt and Genevieve O'Reilly in The Secret
Where is Hazel Stewart now?
Hazel Stewart is also still serving her prison sentence. She was convicted of double murder in 2011 and was sentenced to 18 years at Hydebank Prison in Belfast. Colin implicated Hazel during his own trial and the evidence he gave played a part in her conviction.
She was found guilty of being party to the crimes and disposing of evidence, but despite the evidence against her, she protests her innocence.
The series is proving popular with crime drama fans
Two years after being found guilty, she placed an appeal against being found guilty of the murder of Lesley, but her quest was unsuccessful. She later decided to not appeal her guilty verdict of killing her first husband, Trevor.
Lesley claims that Colin had manipulated and abuse her throughout their time together and was heavily influenced into making criminal decisions. Hazel is due for release in 2029.
Lauren Bradford, the daughter of Colin, was unhappy with the portrayal of her late mother
How did Lesley Howell and Trevor Buchanan die?
In May 1991, Colin gassed his wife Lesley and hid her body in the boot of his car. He then went to the home of Hazel and Trevor Buchanan and suffocated him. Both Trevor and Lesley were played in a vehicle and positioned the bodies to stage a "suicide".
Lesley was found wearing headphones while holding photos of her four children with Trevor in a car filled with exhaust fumes.
Lesley and Colin's daughter Lauren Bradford has slammed The Secret, which originally aired on ITV, for "exploiting a tragedy." Writing in The Guardian, she said: "The character of my mum… is depicted as no more than a down-trodden housewife. It fails to capture her ambition and drive, her wicked sense of humour, her thoughtfulness and warmth."
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