The decades-spanning timeline of the Gilgo Beach killings and the case against Rex Heuermann

Here’s a timeline of the killings on Long Island, how the investigation unfolded and what ultimately led to the arrest of a New York architect.

For more than a decade, a string of unsolved killings on Long Island, New York, known as the Gilgo Beach murders confounded investigators. The case began in earnest with the 2010 disappearance of 23-year-old Shannan Gilbert. The search for her whereabouts led to the discovery of at least 10 sets of human remains along Ocean Parkway and launched the hunt for a suspected serial killer. But the investigation went cold for over a decade. In the meantime, the killings were the subject of a bestselling nonfiction book, a Netflix movie and true-crime documentaries. Authorities announced a major breakthrough in the case in July 2023 when they charged New York architect Rex Heuermann with murder in the killings of three of the four women who became known as the “Gilgo Four.” Heuermann was later charged with four more murders – including the death of the fourth Gilgo Four victim – in incidents dating as far back as 1993. Two forensic laboratories have determined that hairs recovered on six of the seven victims are “forensically tied” to Heuermann or members of his immediate family, or others he lived with, according to a legal filing. In all, Heuermann is accused of killing seven people: Maureen Brainard-Barnes, Melissa Barthelemy, Megan Waterman, Amber Costello, Jessica Taylor, Valerie Mack and Sandra Costilla.