But two weeks ago the skeletal remains of Jennifer Lynn Morris were found down a heavily overgrown ravine and wooded area in Del Monte, CA.
And cops are hoping that with advances in DNA technology, they will finally be able to solve the mystery which has baffled them for more than two decades.
Morris was last seen in January 1983 shopping at the now gone, Saks Fifth Avenue, but after huge search, all they found was her 1977 Ford Pinto in the shopping center car park.
Monterey police Lt. Leslie Sonni told KTVU: "It was a case of someone vanishing without a trace."
She added that even though there was no evidence of foul play, the mysterious circumstances behind the part time student's disappearance led detectives to suspect that she was a victim of foul play.
Now the case is being reclassified as a homicide and investigators will backtrack on the case and apply new technology to recover any evidence that could lead to the identity of the suspect.
Sonni said Morris' father took a leave of absence from work to help find her and became so distraught he could not return to work.
Both he and Morris' mother have since passed away. Police have contacted Morris' two elder brothers after finding her remains.
"They were pretty shocked and are trying to come to grips with it," Sonni said.
Anyone with information about the case was asked to call Detective Mike Bruno at (831) 646-3812 or a confidential tip line at (831) 646-3840.