The story goes back to 1981, when 51-year-old John Blaylock was found dead in Griffith, Indiana. No suspect was ever identified.
However, blood was found at the scene, and kept in the case file.
Fast forward to 2018: Detective John Mowery, Jr. was tasked with reopening the investigation.
His father, retired Detective John Mowery, Sr., who worked the case originally, was among those he interviewed.
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Next came a DNA profile developed from the blood, but there was no match in the national database for offenders.
It was then sent to a private company, which identified two brothers as possible suspects.
One gave a DNA sample that didn't match, leaving his brother, Gregory Thurson, as the likely suspect.
Murder charges followed, and police arrested him in Eugene, Oregon, where he was living.
He has now been extradited back to the area, and is awaiting his court appearance at the Lake County Jail.