The next day, three boys walking along the Sun River in Great Falls found Mr Bogle’s body in an area known as a hangout for teenagers.
He was face down and had been shot in the back of the neck. His hands had been tied behind his back with his own belt. His car’s ignition switch, radio, and headlights were on, and the car was on. His expensive camera had not been taken.
Investigators initially feared Ms. Kalitzke had been kidnapped.
But the next day, January 4, 1956, a county roads worker found his body on a gravel road about five miles north of Great Falls. She had been shot in the head and had injuries that corresponded to a fight or sexual assault, Sgt. Kadner said.
Newspaper headlines described the teens as “victims of lover killers” and recalled a “wide search” for a “brutal killer”.
Over the next half century, detectives investigated around 35 potential suspects, including James (Whitey) Bulger, the notorious South Boston gangster who was convicted in 2013 of participating in 11 murders. Mr Bulger, who died in 2018, had lived in Great Falls in the 1950s and was arrested there for rape in 1951, said Sergeant Kadner.
But no one was ever charged and the case ended in failure.
Investigators turned to genetic genealogy in 2018, after authorities arrested Joseph James DeAngelo, known as the Golden State Killer, and charged him with committing 13 murders and nearly 50 rapes that terrorized California in the 1970s and 1980s. This was the first high profile case to be resolved with genetic genealogy.
“That’s when we really started to look at what evidence we had and whether we could potentially do the same,” said Sgt. Kadner.