Marathon
"On a rainy June morning, tens of thousands of people crowd into Duluth for the city's biggest annual event: the Duluth Marathon. Exhausted runners push to reach the finish line and spectators line the streets to cheer them on. Then, in a terrifying echo of the Boston bombing, there is an explosion along the race course, leaving many people dead and injured ... Within minutes, Jonathan Stride, Serena Dial, and Maggie Bei are at work with the FBI...