They go by names like Bath Salts, Spice, Herbal Incense and even Plant Food, but there's nothing natural about these products. A new breed of synthetic drugs is designed to mimic the effects of marijuana, cocaine, ecstasy and crystal meth. They're cheap, dangerous and legal. Despite a warning label that reads "Not for Human Consumption," an increasing number of people are using these synthetic drugs, often with tragic consequences. Crime Inc. takes you undercover to explore a multibillion-dollar industry.