The three-part series, based on a forthcoming book by investigative journalist and producer Susan Zalkind, follows her as she attempts to piece together the truth behind the 2011 murders of Erik Weissman, Brendan Mess and Raphael Teken in Waltham, Massachusetts. The triple homicide is believed by Zalkind to be the first murders committed by the Boston Marathon bomber, Tamerlan Tsarnaev.