we are now inside the flavela. got the camera. we have got to turn the camera on.elves at the mercy of armed dealers who invite us into one of the wildest scenes i have ever witnessed. you see people are buying the drugs right next to me. they're showing faces. so we are not showing any faces. so this is a -- the dealers who are so concerned about protecting their identities are shockingly young. many just teenage boys. >> he says this is his best-seller. this is five american dollars of cocaine. the best-seller. >> reporter: they follow a strict system with the drugs color coded and sorted by weight. this is $1.50 worth of cocaine. $15 worth of cocaine. like a bargain basement where you hunt for the biggest dose for your money. they're set up near a low cull tra -- near a local train station that delivers a flow of customers all night. >> get a since of being here 30 second. this is an extremely, extremely lucrative operation. >> but we want to know are the profits really worth the devastation that drugs are creating in the dealers' own neighborhoods. >> there are