Smartly dressed and quietly spoken, he portrayed himself as a family man who had been the victim of a terrible miscarriage of justice.
The death of the former Libyan intelligence officer following a battle with cancer brings to an end years of legal and political controversy.
But for the families of the 270 people killed when a New York-bound jet was blown up over the town of Lockerbie in December 1988, many questions remain unanswered.
Megrahi was born in Tripoli in 1952 and educated in the United States and the UK.
By the late 1980s he had become a director of Libya’s Centre for Strategic Studies and later worked in the airline security division, heading up Libyan Arab Airlines’ security operations.
Prosecutors said he used his position to organise, prepare and carry out the Lockerbie bombing and it was claimed he secretly worked for the Libyan Intelligence Service.
Megrahi was linked to the bombing by fragments of clothing that were found wrapped around the remnants of the Lockerbie bomb.
He was identified by Maltese businessman Anthony Gauci, who claimed he sold items of clothing and an umbrella to a Libyan man who looked “a lot” like Megrahi three weeks before the bombing.
His underground role appeared dramatically at odds with the picture of the happily-married father of five who lived with his family in the Tripoli suburbs.
Megrahi was indicted in 1991 after a lengthy investigation by UK and US police forces.
Accused along with compatriot Al Amin Khalifa Fhimah, the pair spent years on the FBI’s “most wanted” list.
After the formal accusation, there followed years of lengthy diplomatic bargaining with Libyan leader Colonel Gaddafi before the suspects were handed over for trial.
It took the intervention of South African president Nelson Mandela before the Libyan authorities agreed to transfer the suspects to a court in a neutral country.
Megrahi and Fhimah eventually faced a trial in 2000, conducted under Scottish law at a specially convened court at Camp Zeist in the Netherlands.
It was one of the most complex trials ever staged, involving 84 days of evidence from 230 witnesses, lasting nearly seven months and costing an estimated £75 million.
Megrahi was eventually found guilty and sentenced to 27 years, while his co-accused was cleared.
In an interview published shortly after his conviction, he denied he was responsible for the bombing.
He told Arabic daily Asharq Al-Aswat: “God is my witness that I am innocent, I have never committed any crime and I have no connection to this issue.”
Two of his children, Khaled and Ghada, attended his trial in the Netherlands, while his black-clad wife Aisha collapsed in the public gallery as his 2002 appeal was rejected.
A first appeal against his conviction was rejected in March 2002.
His lawyers then successfully applied to the Scottish Criminal Cases Review Commission and the case was referred back to the Court of Appeal in the summer of 2007.
But just over a year later he was diagnosed with prostate cancer, which had spread to other parts of his body and was at an advanced stage.
Megrahi had suffered other health problems during his incarceration.
In 2003 he was taken from Barlinnie Prison in Glasgow to the city’s Royal Infirmary after complaining of stomach pains.
He returned to the jail the same day after undergoing tests for a suspected stomach ulcer.
Following the cancer diagnosis, Megrahi applied to the High Court in Edinburgh to be freed pending the outcome of his appeal hearing.
His defence team argued there was a “compelling case” for releasing the cancer-stricken Libyan to live with his family in Glasgow.
But prosecutors argued the gravity of the offence meant he should remain in jail and three judges at the Appeal Court in Edinburgh ruled that he should not be released.
By the time his second appeal eventually got under way, his condition had deteriorated.
A few weeks later an application to have him transferred to serve the rest of his sentence in Libya was lodged, and at the same time Megrahi applied to be freed on compassionate grounds because of his health.
In August 2009, Megrahi dropped his appeal amid speculation that he was to be freed on compassionate grounds by the Scottish Justice Minister Kenny MacAskill
And on the 21st of that month, amid a storm of international protest, Megrahi was released from Greenock Prison and allowed to fly home to his family.
He well exceeded the estimated three months he was given to live, seeing out the 21st and 22nd anniversaries of the bombing back in Tripoli to the disgust of the families of many of the victims.
But while many of the relatives are convinced of his guilt, there are some, particularly in Britain, who believe he is innocent.
Calls have been growing for a public inquiry, but his death means Megrahi will never have the chance to clear his name.
Announcing his decision to send the bomber home to die, Mr MacAskill said Megrahi “faced a sentence imposed by a higher power.”
He said: “It is one that no court, in any jurisdiction, in any land, could revoke or overrule.”