Since ancient times, humans have expressed their passions and their personalities through their collections. But when a collection crosses the line from passion to obsession, ignoring legal, moral and taste boundaries, then it becomes taboo.

Behind the scenes in every society, there are people doing jobs we can barely imagine; people who come into contact with sights, smells and substances that are not only disgusting, but often put their health at risk.

Couples get married at a nudist group wedding. Two dogs get married in an elaborate ceremony. An Indonesian man kidnaps his bride because her family disapproves of the wedding. Some Indian women break local tradition by getting married instead of becoming prostitutes.

In our modern world, old stereotypes are changing. There are now many variations on the traditional ideal of heterosexual monogamy and marriage, like serial monogamy, homosexuality and open relationships.

When people go to extremes with body modification, they provoke fear and disbelief. Take for example, the world's most pierced woman, Elaine Davidson with her 6000+ piercings; Mary Jose Cristerna, with horn implants; pumped up female bodybuilders; and Japan's adventurous bagel-heads, having saline injected into their foreheads for a temporary mutant thrill.

Sex changes are discussed; a profile of a married couple who both switched genders after meeting and falling in love; one person self-identifies as a hybrid - neither male nor female.

Dug, a foot fetishist, has over 300 pairs of shoes and 5+ million photographs of feet. While most collectors keep their collection in their home, Lonnie has allowed his collection to become his home. In Turkey, a potter's strange collection is hidden in an underground cave. What started as a childhood hobby for Lawrence has spun out of control forcing him to rely on his parents.

Fruitarians Aloma and Matthew live off fruit they find in city dumpsters. Puppy play enthusiast Liliane takes her human puppy Jen, aka Tyke, for a walk in the park. Freelance writer Erias walks his dog too, when his sex-worker girlfriend Jessi has company. In Chicago, Matt Daniel and his fiance Casey Levan share an unusual fetish for skintight body suits known as zentai.

In Phoenix, Arizona, a battle for the souls of those said to be possessed is being waged, not by priests, but by five teenage girls. In Colombia, a man's life is crumbling away. Believing he is tortured by demons, he feels he has only two options: suicide or an exorcism. And in Florida, an ex-prostitute and drug addict has become the leader of an evangelical ministry that promises salvation through deliverance from demonic possession.