Karl continues to investigate life's big questions by explores the key factors that shape our people's identities, including gender, accents, hair and clothes, He heads to Los Angeles where he goes for a stroll on Newport beach dressed as a woman, before travelling to Atlanta to meet a man who has made a business out of putting hair back onto the heads of bald men. Karl's journey also takes him to Las Vegas, where he speaks to those who make a living out of looking like celebrities.

Karl meets a group of vigilante superheroes in San Diego as he goes in search of people with unique attitudes towards life.

Karl investigates the alleged benefits of urine therapy as he explores the lengths people go to in order to stay healthy.