One of the most tragic and shocking images ever broadcast to the American people, the Space Shuttle Challenger explosion left our country in mourning. The loss of seven astronauts became more heartbreaking as we learned that the incident could have been avoided if protocols had been different. Hear the emotional recollections of the Challenger commander's wife, two astronauts who were involved in the launch preparation, an engineer for the rocket boosters that failed, and a reporter who thought this would be a routine workday, as they relive the controversial moments that lead to the most notorious day in NASA's history.

The most prestigious race in the country is also Boston's most popular event. Crowds turn out by the thousands to cheer on the runners of the Boston Marathon. The day had always brought the city together, until the one year two suspects tried to tear it apart. When the Tsarnaev brothers planted bombs at the 2013 race, their horrific act killed three people, and maimed many more. Hear from one of the wounded, an on-scene medic, a trauma surgeon, and law enforcement officers who experienced the sudden terror of this cold-blooded act, and the pursuit of justice that followed.