A frail-looking 71-year-old — who is a little unsteady on his feet — will be asked to enter a plea in a Washington DC court next week, charged over what's considered one of the worst terrorist attacks in US history.
The man — known as Mas'ud — is alleged to have built and delivered the bomb that brought down Pan Am flight 103 over Lockerbie, Scotland, in 1988, killing 270 people.
Prosecutors say that — in a confession extracted more than 10 years ago, while he was in custody in Libya on unrelated charges — he has also admitted to setting the timer.
Mas'ud was captured and extradited to the US last month.
His arrest represents a moment of hope for many of the Lockerbie victims' families, who have long campaigned for justice to be done on American soil.
The moment of the crash
It was just after 7pm on December 21, 1988, when the sky lit up red over Lockerbie and residents heard a sound they described as a horrible howling.
"It was like a rushing and screaming noise," one man told the television crews that rushed to the town in the following hours.
He described how "liquid fire … concrete and debris" had rained down on his car.
Reverend Alan Neal — the rector of the local Anglican church — heard something "loud and terrible".
He went out into the night where he met a neighbour who was "all jittery and shaky".
Soon, they came to the shocking realisation that a piece of a plane had landed about 30 or 40 metres away.
All over Lockerbie, those who hadn't been killed — because 11 people on the ground had been obliterated by the falling debris — were leaving their homes to find bodies in the streets and gardens, a huge crater in the middle of the town, and wreckage everywhere from Pan Am flight 103.
In the US city of Albany, lawyer Paul Hudson was taking a call on the office line.
His 16-year-old daughter, Melina, was returning home for Christmas after spending a term at an English school.
"A travel agent called me, who had arranged her ticket, and said that there had been an accident and Melina might have been on a plane," he told ABC's 7.30.
"I rushed home, and my wife was there, and we turned on the TV set and we saw the flames over Lockerbie.
"And, from that time forward, everything changed."
The next day, Paul was on a plane to Scotland, carrying his daughter's dental records.
"We knew in our hearts that this was it."
Majority of victims were Americans
Kara Monetti's afternoon television watching was interrupted by a news flash about the crash.
When her mum came home a little later, she had to break the news that the plane her son, Rick, was travelling home on was missing.
Rick Monetti was one of 35 students from Syracuse University in New York state on Pan Am flight 103.
They'd all been doing an overseas exchange.
There were no survivors.
All 259 passengers and crew on the flight — and the 11 people on the ground — died.
Of the victims, 190 were Americans.
It was considered the most significant terrorist attack on America until September 11, 2001.
"For us, it was a huge deal," said Bill Barr, who was to later become attorney-general in the George HW Bush administration at a crucial time in the subsequent investigation.
In 1991, Bill Barr announced charges against two Libyan intelligence officers, Abdelbaset Ali Mohmed al-Megrahi and Lamen Khalifa Fhimah.
Back in 1988, the crash scene stretched over 2,000 square kilometres.
Police had walked the length and breadth of it, painstakingly searching fields for scraps of evidence.
Shreds of clothing and a fragment of a circuit board eventually led them to Malta and the conclusion that Megrahi and Fhimah had conspired to place a bomb concealed in a Toshiba tape recorder in an unaccompanied suitcase.
The suitcase made its way from Malta to Frankfurt, where it was loaded onto Pan Am flight 103, bound for Heathrow and then New York.
Bill Barr pushed in vain at the time for strong action against Libya and its then-leader, Muammar Gaddafi.
"The impulse was just to add sanctions and I thought they'd be worthless," he said.
"I thought we should strike some obvious military and intelligence targets."
The former attorney-general was also frustrated by the prosecution of the two accused, Megrahi and Fhimah.
They were tried in a special court at Camp Zeist in the Netherlands by three Scottish judges.
In 2001, Megrahi was convicted, but Fhimah was acquitted.
"We had the death penalty, and I think it's likely we would have sought the death penalty. And the Scots obviously don't have the death penalty," Mr Barr said.
"But Scotland, that was the site where the crime was committed, and they had a very strong argument it should be a Scottish case."
To add insult to injury, as far as the Americans were concerned, Megrahi was released eight years later, ostensibly on compassionate grounds because he'd been diagnosed with terminal cancer.
He arrived home to cheering crowds and a welcome by the Gaddafi family and would live for several years still, hardening suspicions among some relatives that the UK had done a deal with Libya.
Rick Monetti's sister, now Kara Weipz, was "beyond" angry.
"I think that that hero's welcome was disgusting and a slap in the face of our loved ones [who] we lost."
Mr Hudson was also "very upset" by Megrahi's release.
"The fact that he was let out much, much too early indicates to me that there are parties that perhaps don't want the full truth to come out."
'Finishing a job that I had started'
The indictment of Abu Agila Mas'ud Kheir Al-Marimi was announced in late 2020, in the closing days of the Trump administration by Bill Barr, then in his second stint as attorney-general.
"For me, it was finishing a job that I had started," he said.
"It was very rewarding for me, personally, to be able to bring those additional charges."
As the charges were announced, Ms Weipz stood next to him.
She was 15 when her older brother died, and she's dedicated much of her adult life to campaigning for truth and justice, currently heading up the organisation Victims of Pan Am Flight 103.
That there has never been a trial in the US in connection with Lockerbie is, to her, "incomplete justice" — so Mas'ud's arrest is "huge".
"It's probably one of the most-significant moments in my life," she said.
Ms Weipz is still working out how she feels about having seen the alleged bomb-maker shuffling into court last week for his pre-arraignment hearing.
When she was younger, she tried to let go of a lot of her anger, but in court, it came back.
"I definitely did have some anger today."
Families hoping to find peace
Mr Hudson is "cautiously hopeful" that Mas'ud will be convicted, but the circumstances surrounding his alleged confession and extradition weigh on his mind.
"One of my concerns is that there may not be enough legally admissible evidence to convict him in a US court," Mr Hudson explained
He will follow as much of the trial, if it goes ahead, as he can in person.
No stranger to Washington, DC, for decades Mr Hudson was a regular guest on Capitol Hill as he devoted himself to advocacy work, lobbying lawmakers after the Lockerbie bombing for improved airline safety and accountability, and for more passenger rights.
He came to court last month, too, when Mas'ud appeared at an initial hearing after his extradition.
However, he didn't come to last week's hearing, because he had a house guest: Reverend Alan Neal, now 95 years old.
The two men formed a lifelong friendship in the aftermath of the Lockerbie disaster.
Ms Weipz, too, has maintained strong bonds with Lockerbie and its people.
She took her three boys there for the first time last summer and she wears a bracelet with Lockerbie's coordinates imprinted on it.
"Lockerbie is just such a sweet town. It is an unassuming town," she said.
"I mean, there's sad memories there, of course, but it's not a sad place. It's a very lively little town.
"To me, it just feels like home."
Ms Weipz will also be watching the Mas'ud case closely.
She hopes the case will bring more information to light about who else might have been involved.
That would help bring peace, she thinks, to the families.
Does she hope for remorse if he's found guilty?
"I think in some ways that might be asking for too much."
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