t is late in the afternoon. Thick clouds hover over the hill towering in front of us. Hundreds of houses and small buildings cascade down the hillside. They resemble Lego bricks carelessly stacked on top of each other—like a jigsaw puzzle of bricks and mortar. I am walking in a long row of about 40 black-clad police officers moving through the alleyways and stairs towards the heart of the favela with stealth. They have raised their guns and are ready to retaliate should we come under fire. Some of them whisper quiet orders at each other. They fear an ambush and do not want to announce their presence to the drug traffickers. There are many places for the traffickers to hide and many blind alleys where the police might get trapped. In some places the passages are so narrow you can touch the walls on both sides of the alley if you extend your arms, and so steep that the stairs have been built to scale the hillside cross-ways. The officers at the front-guard are armed with semi-automatic FAL machine guns. These are war-grade weapons and offer more power and precision than the usual police guns. But above all, the officers tell me, they warrant respect. As we make our way through the neighborhood, they aim their guns at the windows and terraces of the low buildings surrounding us, where the enemy might be hiding. n the last few weeks, the situation in Mangueira has been tense. The favela complex is controlled by Commando Vermelho (CV, the Red Command), one of the three main gangs vying for control over Rio’s favelas.