Ted Green

And there was that shoe print found at the scene, which was the same size that Ambrose wears.

Frank also asked Ambrose about a report from 1972 before Wayne Grieser died in which a friend of Grieser informed authorities Grieser had confessed to him that he and Ambrose drove Mary Kay to the field and that it was Ambrose who killed her.

When Frank brought it up, Ambrose got agitated.

After the interview, Ambrose gave his blood for DNA testing and submitted to another polygraph.

Nothing incriminating was found at his house, and his DNA did not match any found on Mary Kay's items.

In 2000, Frank stopped working the case, but held out hope that one day, something would be found.

What exactly happened in this field in 1969 was still a mystery when Ted Green, in 2015, then the investigator for the Saunders County Attorney's Office, started looking into Mary Kay Hesse's murder.

He had collected reports from all the different agencies that worked the case over the years.

He found memos and statements that had never been filed.

Green says one of those people told him that Ambrose had seen Mary Kay not just at that cafe they frequented, but also around town, and that Ambrose told him he wanted to have sex with Mary Kay.

Green, like Frank, focused his investigation on Joseph Ambrose.

Green says another person told him he had seen Ambrose and Wayne Greaser arguing that night.

Green also re-interviewed a co-worker of Ambrose, who said Ambrose told him after the murder that, quote, I can do six months, but I can't do life.

For Green, this was Ambrose's motive.

Green theorized that Ambrose could deal with serving six months for a parole violation, but not more for attempting to sexually assault Mary Kay.

So you believe he killed her because he was trying to make sure that she didn't report him?

Green was frustrated with the initial investigation's lack of follow-up.

Especially disturbing to him was that Joseph Ambrose's car, that looked similar to this, was long gone and had never been examined.

While Green worked the case, this man, Josh Eberhardt, a friend of Kathy Toll, Mary Kay's cousin, wanted to bring attention to the decades-old murder that continued to haunt the family.

That help came in 2019 when Josh, with the assistance of Kathy, set up a Facebook page tip line.