ON ITS SEASON PREMIERE, ABC NEWS' "20/20" REPORTS ON POLICE TACTICS USED IN NBC'S "TO CATCH A PREDATOR" SERIES STING OPERATION IN MURPHY, TEXAS

ABC News Chief Investigative Reporter Brian Ross' Report Airs on "20/20" September 7;

Plus: An Unprecedented Journey Inside the Living Body, and John Stossel on Healthcare

ABC News Chief Investigative Correspondent Brian Ross explores the tactics used by Murphy, Texas police, the citizen watchdog group Perverted Justice and "Dateline" NBC during a sting designed to apprehend alleged sexual predators in Murphy, Texas for the popular series "To Catch a Predator."

"The police department, the professionals weren't in control of the entire operation," Collin County District Attorney John Roach tells Ross. "They weren't calling the shots. Somebody else was." He says his office warned the Murphy police not to participate, in advance, in writing, stating "[we're] in the law enforcement business, not show business." Ultimately Roach declined to prosecute any of the 23 men arrested in the "Dateline" operation, citing both jurisdictional issues and problems with how evidence was collected and the arrests were made. One man, an assistant district attorney, William Conradt Jr., committed suicide as the police stormed his home on a Sunday afternoon with NBC's cameras waiting outside. His sister is now suing NBC and Perverted Justice, saying they caused his death.

"The sting operation left a trail of destruction in the community of Murphy. It shattered lives. It shattered careers," says Walt Weiss, a former Murphy police detective who played a big role in the operation and who regrets the way it was handled. "I'm truly ashamed to have been part of that."

Murphy Police Chief Billy Myrick defends the operations and denies that his department ceded control to NBC or Perverted Justice. NBC News has defended its actions but declined repeated requests to have anyone appear on "20/20." Ross' three month investigation airs on "20/20's" season premiere, FRIDAY, SEPTEMBER 7 (10:00-11:00 p.m., ET) on the ABC Television Network.

Plus: "20/20" offers the first look at a National Geographic Channel documentary "Inside the Living Body," a unique, cradle-to-grave depiction of the inner workings of our bodies. Stephen Marsh, a cellular biologist who is the executive producer of the documentary, says that, given the advances in technology, "the whole idea was to make a seamless voyage through one body. We all have external appearances that are very different, but our internal lives are surprisingly similar." More than 200 scientists and experts were recruited to advise the makers of the documentary, which premieres September 16 on the National Geographic Channel. Bob Brown reports.

And: John Stossel discusses healthcare in a report on medicine in Cuba. Michael Moore says, "If there's one thing they do right in Cuba, its healthcare." Stossel looks at whether Moore gets that story right. Stossel has a one-hour special on healthcare airing September 14.

"20/20" is anchored by Elizabeth Vargas and John Stossel. David Sloan is executive producer.