Nothing could have prepared me for what I'm about to see.
I'm in a fancy villa in a posh part of Tripoli, walking through the garden past a huge plastic children's swing set and a trampoline that dominate the lush green lawn. A young man is filling a large swimming pool.
All this in a city where water is running out. I've not had a shower or washed in running water for three days. The al-Megrahis, it seems, are not short of money.
This villa connects to another, equally palatial but far more contemporary. It's clad in modern ceramic tiles, like something you'd see in trendy London neighborhood.
As I walk up the grand staircase towards the front door, I'm mentally composing my questions - what I'll ask Abdel Basset al-Megrahi first. Did you do it? Did Gadhafi give you the orders?
I've been waiting for the moment for a long time.
When Pan Am Flight 103 was blown out of the sky over Lockerbie, Scotland, I spent the night trying to get the first live pictures back to London and saw the first grainy images revealing the horror of what had happened. I'd covered Megrahi's trial in Camp Ziest in the Netherlands, a tiny patch of Scotland on Dutch soil created out of a compromise with Libyan ruler Moammar Gadhafi to get the trial in a Scottish court and begin Libya's long slow rehabilitation with the West.
When he was released from a Scottish jail two years ago, on compassionate grounds, given only three months to live by doctors after serving eight years of a life sentence, it seemed that perhaps the time had come to learn his secrets.
A few weeks later, I saw him, and officials told me I might get to interview him. It was a lie. They had too much to hide and did their best to keep him away from journalists.
Now, with Gadhafi gone, the moment had come. His family invites me inside his home to meet him.
Through the doors, after the harsh sunlight, it's darker than I expect. My eyes quickly adjust, and I'm scanning the large hall looking for the gray-haired al-Megrahi.
The last time I saw him, he was in a wheelchair. He'd looked weak, worn out by meeting so many family and friends on his return, I was told.
But I thought at least we could have a conversation. Maybe it would be a little slow, but I am ready, my questions clear. We walk towards a rather grand staircase. Then, just as I expect to begin the climb, we turn abruptly left into a tiny, high-ceilinged room lined with red and tan wallpaper, patterned in the way elderly men seem to like in their studies.
I was expecting al-Megrahi to be in a comfy armchair, but he was not.
Where the chair might have been, in the corner facing the door, was a metal hospital bed - the type with wheels that can raise and lower a patient's back. Beneath the blankets was al-Megrahi, eyes shut, inert.
At first I didn't know what to do. My carefully thought-through questions were useless. I was stunned. Was I being shown him so I would see with my eyes how sick he was? Should I try to talk to him?
I took in all I was seeing. The oxygen mask on his face, the old, sick lady - his mother, I was told - at his bedside, the drip hanging a foot from his head. His skin seemed paper-thin, his face sallow and sunken.
Was this all a drama for me? Was this real, or had they invited me after my 15-minute wait outside after the "stage" was set?
My fingers are fumbling on my camera. I'm still in shock. This was so much not what I was prepared for.
In the two decades since the bombing, which killed 270 passengers, crew and townspeople below, it seemed the secrets of the attack would die with the bombers. Al-Megrahi had promised to prove his innocence. With Gadhafi gone, I thought this could be the moment he points the finger of blame.
The air feels heavy in the room, silent aside from a quiet hissing from the oxygen bottle by the bed. Then his son Khaled speaks.
He tells me his father hasn't seen a doctor since they rescued him from a hospital before Tripoli fell to the rebels, whom he said looted all the medicine from their house
"We just give him oxygen," his son says. "Nobody gives us any advice. And some food by injection (drip) ... If you see his body he is weak."
As we speak, I watch to see if his father stirs. There is no movement. His eyes remain shut. Khaled keeps talking.
"What about demands he finish his sentence in Britain?" I ask.
"My dad, he's still in house," his son says. "If you send him to Scotland, he will die by the way. Here or there."
Although neither of us know it, at that moment, he'll soon be relieved. This evening, the National Transitional Council announces they'll leave al-Megrahi be and won't send him back to Britain.
The family wants me to leave. They are polite. We talk in hushed whispers. They'd told me when they first let me in that I had only two minutes to be with him, and it's been 10 already.
They want al-Megrahi to spend his last days in peace, they say, away from reporters and their questions. But before I leave, I must ask the toughest question of all: How much longer does he have left to live?
"Nobody can know how long he will stay alive. Nobody knows," Khaled says. His eyes droop. His face is drawn, too, his voice wavering and emotional. This is a family already grieving.
Whatever secrets al-Megrahi had will soon be gone. As I leave, I'm still shocked by what I've learned. The world is about to lose one of the few people who can piece together what really happened that dark, wintry night, 29,000 feet over Scotland.