Witness to a Nightmare - S1.E3

On an evening in March of 1990, a knock comes at the door of Donna Willard's Philadelphia residence, and she finds herself face-to-face with a hooded gunman. He shoots Donna twice, killing her instantly, as her twelve-year-old son witnesses the murder from the peak of the stairs. For months, the hunt for her killer leads investigators on a maddening series of dead ends.