Denise Marie Seamen, 17, disappeared from Tinicum, Pennsylvania on the evening of May 10, 1975 after leaving home to meet her boyfriend, James Koenig, at MacDade Mall in Glenolden. She never arrived at the mall and was reported missing by her boyfriend. On October 17, 1975 skeletal remains found in a marshy area of Tinicum Township were identified as Denise’s; she had been shot in the head and her death was ruled a homicide.

Investigators treated Denise’s killing as part of a troubling pattern: several young women from the area vanished in the mid-1970s, including Mary Ann Lees, Layne Dorothy Spicer, Debra Jean Delozier, and Elizabeth Lande, whose body was never recovered. Despite an extensive investigation and multiple suspects considered, no arrests were made and the case remained unsolved.

What information about Denise, her movements that night, or anyone who might have seen her heading toward MacDade Mall could help move this cold case forward?