Semi-Final 1: Tilly

Dateline NBC presents in-depth coverage of news stories. Rather than just reading news reports, as most news shows do, the reporters for this show research their subjects and interview the people closely involved to create an informative work of investigative journalism.

Long before banks, ATMS and check-cashing services, there were pawn shops. Pawning was the leading form of consumer credit in the United States until the 1950s, and pawn shops are still helping everyday people make ends meet. Pawn Stars takes you inside the colorful world of the pawn business. At the Gold & Silver Pawn Shop on the outskirts of Las Vegas, three generations of the Harrison family - grandfather Richard, son Rick and grandson Corey - jointly run the family business, and there's clashing and camaraderie every step of the way. The three men use their sharp eyes and skills to assess the value of items from the commonplace to the truly historic, including a 16th-century samurai sword, a Super Bowl ring, a Picasso painting and a 17th-century stay of execution. It's up to them to determine what's real and what's fake, as they reveal the often surprising answer to the questions on everyone's mind, "What's the story behind it?" and "What's it worth?"

For generations of Americans, food titans like Henry Heinz, Milton Hershey, John and Will Kellogg, C.W. Post and the McDonald brothers have literally been household names, but you don't know their stories. Before they were brand names, they were brilliant, sometimes ruthless, visionaries who revolutionized food and changed the landscape of America forever. This miniseries event will tell the fascinating stories of the people behind the food that built America – those who used brains, muscle, blood, sweat and tears to get to America's heart through its stomach, and along the way built cities, invented new technologies and helped win wars.

History's Greatest Mysteries will investigate a wide range of historically compelling topics and the mysteries surrounding each including the Titanic, D.B. Cooper, Roswell, John Wilkes Booth, and more. Each program within the franchise will showcase fresh, new evidence and perspectives including never-before-released documents to the general public, personal diaries and DNA evidence to unearth brand-new information about these infamous and enigmatic chapters in history.

90 Day Fiancé offers a unique look into the world of international dating and matrimony. Using a unique 90-day fiance visa, the K-1 visa, four women and two men will travel to the U.S. to live with their overseas partners for the first time. The couples must marry before their visas expire in 90 days, or the visiting partner will have to return home. They'll have to overcome language barriers, culture shock and skeptical friends and family -- all with a clock that starts ticking the moment they step foot on U.S. soil. The stakes are incredibly high as these couples are forced to make a life-altering decision: get married or send their international mate home.