Taboo (National Geographic Channel)

National Geographic's provocative documentary series TABOO raises questions about what's socially acceptable among subcultures in the United States and around the world. Each episode presents groups who engage in norms, traditions, and rituals that fall outside of the mainstream -- from gender bending and eating rats to scarification (the art of creating scars on the body by piercing, tattooing, or burning) and body modification. These acts are often seen as strange, unacceptable, or forbidden by those who don't perform them.

Taboo doesn't attempt to change people's minds about what's "right" or what makes something an acceptable social practice. Instead, the series focuses on exposing viewers to people and practices that they might never see otherwise.

While the series is quite educational, the seemingly bizarre and sometimes-grotesque imagery can create a carnival-like quality that's more entertaining than informative. But the shocking nature of the show's visual images also pushes viewers out of their comfort zone -- they're instrumental in challenging people to open their minds and consider the fact that every cultural group has their own definition of what's "normal."