The last time anybody heard from John Kelly Gentry Jr. was in a postcard from Southern California.
It was 1983 and the 30-year-old Michigan man had recently disappeared after his 25-year-old girlfriend, Barbara Gerber, was discovered stabbed to death at her home in Summerfield Township, Michigan, according to Reuters.
Days later, police discovered the bludgeoned body of William Veith, an Ohio man who investigators believe was also in a relationship with Gentry, Reuters reported.
Investigators eventually decided that Gentry was responsible for both killings. He has eluded police for more than three decades and now investigators believe they know, in part, how he avoided detection so successfully.
"The U.S. Marshals Service received information in the last five years that Gentry was possibly living in California as a woman, that dresses as a woman," Monroe County, Michigan, Sheriff's Detective Jeff Smith said.