The idea was to get stuck in straight away: get the shots, get the interviews, get on the plane.
But at 8.15 on a grey morning in São Paulo's crack district I stopped. And stood. And stared.
In the middle of a busy district was a quadrant of streets where buildings had been demolished.
There was a mosh of people milling around one intersection … maybe a couple of hundred sitting, standing, chatting, dancing, shouting. And smoking.
Look more closely and I could see the thin shiny metal pipes held in grubby hands and pressed up against craving lips.
As a journalist you're meant to be objective. But two competing impulses were fighting in my brain. Pity and revulsion. I'm not proud of the latter.
It wasn't the squalor everywhere you looked - I've seen that plenty of times before. It was the slightly carnivalesque atmosphere, the deranged edge to it all.
The fact that this was like a scene from an 80s zombie movie but masquerading as normality.
And the brazenness of it. It was 8.30am. They were busy getting high. And they didn't give two hoots what anyone else thought.
Surrounding this quadrant of roads were dozens of police and public health workers. An enormous investment of taxpayers' money to contain this problem … and possibly to try and cure it.
Police stood on every corner. Some had rubber bullets - "a deterrent," they told me, "we only need to use them every few months." They explained that there were 50 cops on duty during the day and 50 at night. Imagine that wage bill, multiplied by 365. Staggering.
And there were doctors, ambulances, psychiatrists, social workers on hand too. Armies of them.
After years of sending in the police to clear the streets of crack addicts, which wasn't a long-term solution, they're now trying a new policy called "Open Arms" where people are given a few hours work a day (eg. road sweeping) in exchange for a room in a hostel, meals, £4 in cash plus the whole spectrum of rehab resources.
It is expensive. And some of those we spoke to were managing only to reduce crack smoking, not eliminate it. But there are successes.
One former addict stuck out. Not just because she was now clean of drugs - she shone, particularly when she opened up in interview with that fantastic eloquence that is common to pretty much all Brazilians.
Poliana was 23 but looked older. Her mother was a crack addict who'd been knocked over and killed by a car after wandering out into the road while high.
Cradling her two-year-old daughter on her lap … Poliana explained that she'd taken the child to the hospital aged six months because she wasn't growing.
Pale, with her eyes rolling back in her head, the doctor recognised the signs immediately. He said the baby was having an overdose because Poliana had been breastfeeding after smoking crack.
The infant was near to a coma. Six months before this was the doctor who'd delivered the child … now he was telling the mother that the same child would soon die - unless Poliana stopped using crack.
Now both mum and daughter look well. They are happy. They are bouncing. But they are still in crackland, living with the father who continues to use the drug.
As Poliana carried Victoria through the posse of addicts, still getting high on crack, some of the more sober ones were ruffling the little girl's hair and calling her sweetly by name.
It was almost touching but at the same time deeply troubling. This was the child's life. This was her extended family. But was this her future?