Episode 3: Justice for Gwen?

In 2001, Dr. Sharon Pritchett’s life is upended when her oldest sister, Gwendolyn Williams, is found strangled to death behind a 99 cent store. Her murder is seemingly random until Pritchett learns that her sister’s case is a part of a mysterious pattern of 51 murders that has plagued the city of Chicago for the last two decades.

With little momentum, the case goes cold until Pritchett discovers a major backlog with DNA testing in the Illinois State lab system that has kept the truth of who is behind her sister's murder buried away for years...