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.

The largest terror attack in our nation's history left images seared into our conscience that will never be forgotten. But for those caught in the middle, the memories are as strong today as they were in 2001. Hear the harrowing experiences of a trader who worked in the World Trade Center, a firefighter, a Port Authority officer, an ER doctor, an NYPD rescue worker, and a news reporter who were at Ground Zero, as well as a Pentagon contractor, an Airfone operator communicating with Flight 93, and the head of FAA operations as they experienced the tragic unfolding of a day none had dreamed possible.