In Bogota grim, gritty reality hits hard. We meet Michel, a young Frenchman whose week long holiday in Colombia has been unexpectedly extended. Short of cash back home in France he came to Colombia, where he had heard a fortune could be made carrying cocaine through customs.

"I thought I could get through and return to my country with no problem. But no, I got caught." Michel is now serving a six-year sentence in one of Colombia's toughest jails. "They're all armed, either with knives or even with scissors and pens. You're waiting in line to eat and bam, they get you..." The men he shares a cell with are mostly convicted murderers.

"You arrive with no problem. You travel with no problem" and then, at the other end, "everything that goes in comes out. As simple as that. And 6000 euros richer." We have been approached by cocaine smugglers who have heard we will work for them. They take us to their workshop where our hidden camera rolls as we watch a smuggler being prepared. Powder is poured into the finger of a latex glove and packed down, before being covered in a coating of wax. Each capsule is the size of a large almond and contains 6g of cocaine. "How many capsules will you swallow?" we ask, "119" the answer comes back.

We move swiftly to our next destination. We had been warned that, "anyone who talks has to take the consequences." We don't want to risk the smugglers finding us out, and take refuge with an Anti-Drug Hit Squad preparing to launch an attack.

"The grenade...the grenade. Do you see the smoke?" Three heavily armed helicopters swoop down on the Amazonian jungle. Major Santamaria and his men have spotted an illegal cocaine factory. The operation is fraught with danger: 20 Government Commandos die every week in these raids. "The fact that they haven't shot at us doesn't meant there aren't enemies in the area." Mines and traps make the soldiers wary. They force a local farmer to lead them to the factory. Then their fury is unleashed. Teams of commandos throw gallons of petrol everywhere. Others snatch account books and a GPS away just in time as flames leap into the air. "Lets get out of here. Quick!"

High up in the Andes the battle takes a different form. "They come straight at us and pee on us. That's how we say it here," explains farmer Don Jairo, "All the fields are burned. My vegetables, my carrots." This is a US concept: poison the jungle, and no drug can grow. And so, the tentacles of Colombia's greedy drugs economy stretch out even to this beautiful, Andean mountainside.

Elite commando raids in remote jungle locations, teenage tourists banged up in maximum-security jails and dodgy back alley deals: this is a story no one could make up. Sit back and hold on tight!