Ever wonder what the big deal is about bath salts? Watch an exclusive clip from this week's episode of NatGeo's "Inside: Secret America" (Wed. July 10 at 10:00 p.m.) to get a glimpse of why this dangerous trend is trending with dealers. 

On the episode, investigative journalists Mariana van Zeller and Darren Foster explore the synthetic drug craze in America. They travel to the South, where local law enforcement is trying to shut down manufacturers and distributors — a difficult task, because the chemicals used are constantly changing and the law cannot keep up. They also visit former and currently active Marines in San Diego, who share their stories of synthetic drug abuse and explain that these types of drugs do not show up on standard drug tests. They go undercover with the Marines to local smoke shops to see how easy it is for someone to buy synthetic marijuana and bath salts.

What do you think about bath salts? Will you be watching "Inside: Secret America"? 

Liane Bonin Starr is an author, screenwriter and former writer for EW.com. Her byline has appeared in the Los Angeles Times, Variety and a lot of other places. Her last book was called "a scandalously catty, guilty pleasure" by Jane magazine. Expect the same from Starr Raving.