The Yakuza is one of the most powerful organized crime syndicates in the world. It is Japan's not-so-secret version of the Mafia, with 85,000 members who trace their roots back to 17th century Samurai warriors.

Deeply embedded in Japanese business and culture, the Yakuza also have their tentacles into this country and American law enforcement knows it.

One man they keep a close eye on is Tadamasa Goto, a ruthless "Godfather."

Ordinarily such a notorious mobster wouldn't even be allowed into the United States, but Tadamasa Goto not only got into the country, he jumped to the top of a long waiting list for a life-saving liver transplant at UCLA Medical Center.

"What does it mean in Japan to be a Yakuza?" correspondent Lara Logan asked a Yakuza boss - a rival of Goto's who agreed to be interviewed if 60 Minutes masked his identity and did not use his name.

"To be a Yakuza in Japan is to live an unalterable way of life. It's not an occupation. It's to follow and explore the lives of the Samurai, the code of the Samurai," the man told Logan.

Asked how a person can tell if someone is a Yakuza, the man told Logan, "It's the smell….The smell of another beast."

"When you join the Yakuza, they become your family," Jake Adelstein told Logan.

No American knows more about the inner workings of the Yakuza than Adelstein. He has spent the last 15 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 a lot of construction companies. So, you know, you're pouring a new building. You throw the body in, like, the cement. And nobody ever finds it. The buildings go all up, all the time in Tokyo," Adelstein explained.

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 their entire body, marking them for life.

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," the anonymous Yakuza boss told Logan.

He was introduced to "60 Minutes" by Jake Adelstein in downtown Tokyo. Beneath his expensive suit, his body is a canvas, like many Yakuza, covered with intricate tattoos.

"Physically, the tattoos take their toll on your body," Logan remarked.

"The tattoos are so dense that it's very hard to sweat, which means when you can't get rid of the toxins in your body, that's also very hard on the liver," Adelstein explained.

What's also hard on the liver is the hedonistic lifestyle of the Yakuza.

As she walked down the main street of Tokyo's entertainment and "red light" district, Logan explained, "This is traditional Yakuza turf. They run everything from the girls to the sex, to the drugs. But the modern Yakuza is a different animal, adding corporate takeovers, financial fraud and insider trading to their criminal portfolio."

That's how Tadamasa Goto made most of his money. According to Japanese police files, he amassed an estimated billion dollar fortune through nearly 100 front companies.

He is one of the richest and most violent godfathers in Japan. That's why he's known to U.S. law enforcement as the "John Gotti of Japan."

But there was one thing Goto's power and money couldn't buy him in his homeland. He had liver disease and desperately needed a transplant.

Culturally, the Japanese don't believe in organ donation, so to get a new liver, he needed to come to the U.S. For a Yakuza, that should have been a problem, said Mike Cox, the chief of immigration and customs at the U.S. Embassy in Tokyo.

"We want to be a welcoming country, the United States. But certainly we don't want the Yakuza coming to the United States," Cox told Logan. "They have extensive criminal histories here in Japan. They are members of criminal organizations. For both of those reasons they would be ineligible to enter the United States."