adelstein. he spent years in tokyo, investigating and writing about the mob. >> generally speaking, yakuza get rid of bodies by dumping them in the foundations of buildings. they own lots of construction companies. so, you know, you're pouring a new building, you throw the body in the cement, and nobody ever finds it. >> so when you look around at all these tall buildings in tokyo... >> you could be looking at a graveyard. >> it's impossible to miss the mark of a yakuza: severed fingers. tradition demands when a mistake is made, they chop off their own finger to atone and present the severed part to their boss. many have ornate tattoos that often cover the entire body, marking them for life. [traditional japanese music] but unlike the mafia in america, yakuza don't hide their membership in the mob because it's not illegal in japan to be a member of organized crime. and they are so much a part of japanese culture, they parade openly. >> right now, we don't hide the fact that we're yakuza. >> this