Serial killer pleads guilty to eight murders in case that haunted Long Island

After initially pleading not-guilty, Heuermann ultimately pleaded to the murders of: Melissa Barthelemy, 24, Megan Waterman, 22, and Amber Costello, 27, Maureen Brainard-Barnes, 25, Jessica Taylor, 20, Valerie Mack, 24, Sandra Costilla, 28 and Karen Vergata, 34.