The sole surviving member of the terror cell that massacred 130 people in Paris in November 20 was a pot-smoking party man who dabbled in petty crime before falling in thrall to the Islamic State group.
All eyes will be on Salah Abdeslam on Wednesday when he goes on trial in Paris along with 19 others over the worst terror attack in France's history.
But those hoping that the so-called 10th man of the Islamic State attacks will tell all about what drove him to be part of the macabre plot risk being disappointed.
Since his arrest after a massive four-month manhunt that ended in a shootout with police in Belgium, Abdeslam has maintained near-total silence on his role in the bloodshed.
Nine other gunmen and suicide bombers died in the carnage, including Abdeslam's brother Brahim, who blew himself up in a bar.
Like Brahim he was equipped with a suicide belt, but he did not activate the device, which was found in a rubbish bin in southern Paris several days after the killings.
The 31-year-old, who has French citizenship but grew up in Belgium, is accused of playing a key logistical role in the attacks.
He drove the three suicide bombers who blew themselves up outside the Stade de France to their destination.
Abdeslam also rented cars and hideouts and drove across Europe in the months before the attacks to collect jihadists who had slipped into the continent unnoticed among masses of migrants.
He told police shortly after his arrest that he too had been primed to carry out a suicide attack at Stade de France, one of six venues targeted in the Paris attacks, but that he had backed out at the last minute.
Investigators have cast doubt on that claim, saying they believe he was intent on seeing through his mission but was hamstrung by a faulty explosive belt.
Whatever the outcome of the trial he is likely to spend many years behind bars, being just three years into a 20-year sentence for attempted murder over the firefight with Belgian police.
One of the world's most-wanted suspects spent the immediate aftermath of the Paris attacks eating fries and chatting with two unsuspecting teenagers in the stairwell of a Paris high-rise while waiting to be driven across the border to Belgium.
It was only when his mugshot was released by police days later that the pair realized the man who was looking over their shoulder at a news item about the attacks was one of the chief suspects.
In the Brussels suburb of Molenbeek, where he grew up, Abdeslam was known for his bad-boy lifestyle of petty crime, smoking weed and gambling. An inveterate clubber, he also had a reputation as a womanizer.
His multiple brushes with the law included a conviction for attempted robbery in 2010 with a childhood friend, Abdelhamid Abaaoud, the coordinator of the Paris attacks who was shot dead by French police in a siege a week later.
Abdeslam, who grew up in a family of five children, worked as a technician for the Brussels tram network but was fired for skipping work in 2011.
In later years, he spent much of his time hanging out in a cafe run by Brahim.
Friends of the brothers say they became hooked on the Islamic State after the Sunni radical group proclaimed a caliphate in Iraq and Syria in 2014.
They say they stopped drinking, showed a new-found interest in Islam and huddled with other would-be jihadists to imbibe IS propaganda.
In February 2015, Belgian police summoned Salah Abdeslam to discuss Abaaoud who had appeared in a gruesome video from Syria, showing him driving a pick-up truck that was dragging mutilated bodies to a mass grave.
"Apart from the jihad, he's a good guy," said Abdeslam, who claimed to oppose IS thinking despite having also shown interest in traveling to Syria.
His rare public utterances since his arrest have shown he remains wedded to Islamist ideology.
At his Belgian trial in 2018 he rejected the court's legitimacy saying he trusted only "in Allah.”
During questioning by a French magistrate in 2018 he justified terror attacks on France saying: "Muslims defend themselves against those who attack them."
An unrepentant Abdeslam is also believed to be the author of a letter found by Belgian police on a computer in 2016, in which he declared he "would have liked to be among the martyrs" and is ready to "finish the job.”
His former Belgian lawyer, Sven Mary, was scathing about his client in a newspaper interview in 2016, although this is disputed by his lawyer in the current trial, Olivia Ronen.
"He has the intelligence of an empty ashtray. He's extraordinarily vacuous," Mary said.
"I asked him if he had read the Koran, and he replied that he had researched it on the internet," Mary said.