Trying to lie still in a Malaysian jungle, while being bitten - more like consumed - by a swarm of angry fire ants had me questioning whether the story we were pursuing was worth it.
But the figure of $26bn kept popping into my head. That is the estimate by one wildlife protection group as to how lucrative and expansive the yearly illegal trade in animal trafficking has become.
Things have gotten so out of hand that scientists predict more than 40 percent of South East Asia's animals could be wiped out in this century.
And so there we were: A cameraperson and myself, hunkered down in the back hills of Penang, Malaysia, trying to avoid a sentry and a barking guard dog, which looked as if it would be tearing into the jungle and into us at any moment.
We had been carefully making our way around a property linked to Anson Wong, one of the world's most notorious wildlife traffickers.
In 2010, when authorities burst into this place, they found an incredible array of animals, including Bengal tigers.
On the trail
The raid followed the arrest of Wong, also known as "The Lizard King", who had been caught, just days earlier, at the airport in Malaysia trying to smuggle boa constrictors into Indonesia. While it was his second conviction, he served just 17 months of a five-year sentence.
Released in February 2012, sources close to the Lizard King told us that, within days, he was back plying his trade. That information is what led us to this property, where we were trying to get a peek of what, if anything was being kept there.
In fact, our arrival in Penang was the tail-end of a year-long investigation. With the help of several informants, we had tracked the Lizard King’s network of "agents" to source countries including Madagascar, where endangered Ploughshare Tortoises could be found and sold off for $25,000.
The Ploughshare is reported to be the prized animal of choice for Wong, because of its value and resilience in surviving transport.
From there, we followed the often-used smuggling routes into South East Asian countries such as Thailand, Indonesia and Malaysia, where illegally trafficked wildlife is often housed, and then sold off to buyers around the world.
For most of our investigation, The Lizard King eluded us. But our decision to check out his rural Penang property proved fruitful.
"Can you see what’s inside those pens?" whispered our cameraperson.
After what seemed like an eternity, the guard and attack dog, having not seen or heard any more movements, had seemingly lost interest and moved on.
It allowed us to change our vantage point, and it was from this new position that we spied what looked like new enclosures.
"I think there's something big inside," he said.
Slowly we snuck closer. And then we noticed movement. There were three large cats inside - and not of the household variety.
From our pictures, wildlife experts would later determine they were Serval cats from North Africa.
A visit to another stash-house in Penang, once again linked to Anson Wong, turned up Albino pythons, lizards and a range of other snakes, including vipers. All, according to an employee there, were being prepared "for sale and shipment elsewhere".
The one question we kept asking ourselves is how was this possible?
Following his 2010 conviction, the Malaysian government's wildlife department, Perhilitan, had publicly announced that Wong and his family were banned from holding any business licences or permits to trade in wildlife.
The minister in charge of the department had confirmed to us in an interview that that ban should stand to this day.
Yet, when we searched a slew of public records, we found Wong and his wife still running several companies specialising in the export of animals - all of which had been signed off by authorities.
N Surendran, a lawyer and opposition minister of the Malaysian parliament, has for years called on Perhilitan to be investigated for corruption. When we presented our evidence to him, he believed that Wong could not have operated alone without the "complicit aid of authorities".
It would be far from surprising if that was true. To infiltrate the black-market underworld of wildlife trafficking, we had posed as dealers. Time and again, smugglers and "distributors" – some who had worked closely with Wong for more than 30 years – would tell us that customs and wildlife officials were regularly "bought off".
They also told us that, at times, authorities in certain countries would get too "greedy", and go "rogue", where they would start seizing shipments they knew were coming through a port or airport, and sell off the animals themselves.
After it having happened several times in one location, dealers would be forced to switch their routes, and try to find more "reliable officials".
It speaks poorly of the worldwide effort to tackle wildlife crime. This year marked the 40th year of the Convention on International Trade in Endangered Species (CITES) - a pledge made by 179 countries to bring an end to animal smuggling and save the earth's most precious species.
Yet the current plight of rhinos and elephants in Africa, and the evidence we uncovered in our investigation show those efforts have proven far from effective – you could go so far as to call it an utter failure.
This year, the UN listed wildlife smuggling as a "serious crime", on par with the trafficking of drugs and people. It is an attempt to empower nations, and enforcement agencies and convince them to get tougher.
But is there a will?
When asked how quickly the world could put an end to wildlife crime, one smuggler said to us:
"It would take just one day. All you have to do is get rid of officials on-the-take, and then it becomes impossible for us to move our supplies around," he said. "But then again, that'll never happen."
Our documentary, we hope, underlies how desperate the situation is for many of the world's most iconic species, along with the challenges involved in tackling what is a reprehensible crime.
At the end, we did manage to track down the Lizard King, to ask him directly whether he remains at the helm of his global wildlife-trafficking empire. His answer spoke volumes.
Follow Steve Chao on Twitter: @SteveChaoSC