Are You for Real?

Are you everything you say you are? Or, like many people, do you have two faces -- one you present to the world and one that's the real you? In a special hour, "20/20" brings you stories of people who've re-created themselves and their histories or created careers based on half-truths. Is it lying -- or is it just stretching the truth? Is there a difference?

'Self-Made Man'

JuJu Chang talks with female author Norah Vincent, who transformed herself from head to toe to go "undercover" as Ned Vincent, successfully infiltrating the inner sanctum of a man's world. From boys' bowling night out to picking up and dating women to living as a monastery trainee and attending a men's-only therapy group, Vincent was able to experience the world women rarely get to see. "I wanted to enter males' spheres of interest … and see how men are with each other. I wanted to make friends with men. I wanted to know how male friendships work from the inside out," Vincent tells "20/20" in her first televised interview since writing her book, "Self-Made Man," about her secret experiment.

Vincent tells Chang what she learned from being a man -- and her revelations may surprise you. "This wasn't just a stunt. … It was about finding something out about the human creature, and I learned it the best possible way because I went through it."

Infomercial King

John Stossel takes on the infomercial king Kevin Trudeau, who says his books on natural remedies offer preventions and cures for virtually every disease. His infomercials filled 2,000 hours of airtime last year, and his book has been on the best-seller list for the past six months. But who is this infomercial king who has made a fortune selling the unproved, and why do so many people follow his claims?

Legendary Hoaxes

Hoaxing is one of the oldest games people play, pretending to be something they are not. People have been playing it for sex, power, ego and money for centuries. So why is it sometimes so easy to play with the truth, and what are the classic ingredients of a successful hoax? Bob Brown looks at notorious hoaxes, including the recent headline-making dubious memoirs and the false claim of finding a finger in a container of Wendy's chili.