*The following article is in regard to the murder of four children. Reader discretion is advised.
Timeline: The Threinen murders
- June 15, 1975 — Dahrlyne Cranfield (12) and Robert Grubesic (9) disappear while biking near the river.
- July 26, 1975 — Cathy Scott (7) and Samantha Turner (8) go missing in Saskatoon.
- August 12, 1975 — David Threinen is arrested; he confesses to killing all four children.
- August 13–14, 1975 — The children’s bodies are found; coroner confirms cause of death was strangulation.
- February 12, 1976 — Threinen pleads guilty and is sentenced to life in prison.
- 1995 — Parole denied, 20 years after the murders.
- 2025 — Threinen remains in custody under Correctional Service of Canada.
SASKATOON — August 2025 marks the anniversary of one of Saskatchewan’s most horrific and arguably most forgotten-about murders — those of Dahrlyne Cranfield, Robert Grubesic, Cathy Scott and Samantha Turner of Saskatoon. David Threinen was convicted of their murders and is currently serving a life sentence.
Although the Correctional Service of Canada cannot comment on where Threinen is currently being held, they can confirm he is still alive and being held under the jurisdiction of the Correctional Service of Canada.
Following is a recounting of the circumstances according to public reporting.
On the afternoon of June 15, 1975, Dahrlyne Cranfield, 12, and her friend Robert Grubesic, 9, decided to go for a bike ride and were last seen as they rode their bikes down to the Saskatchewan River in Saskatoon and locked them up along the 800 block of Saskatchewan Crescent East.
After not returning home that afternoon, both Dahrlyne and Robert were reported missing the same day.
Although the Saskatoon police searched where their bikes were found along the river with dogs, nothing was found.
On June 18, a woman reported seeing a man described as being 17 to 25 years old, about 5’8” with a slim build and blonde hair to his shoulders, luring Dahrlyne and Robert away and down an alleyway, holding their hands.
Over the next few days, multiple rewards for any information on the missing children were put forward. They added up to $10,000 on June 25, 1975.
As information and leads dried up, the Saskatoon police had little to continue going on. A final article about Dahrlyne Cranfield and Robert Grubesic was published in the Saskatoon Star Phoenix on July 26, 1975.
At this point, they had been missing for 42 days.
The same day, Cathy Scott, 7, and Samantha Turner, 8, went missing. One of the last sightings of the two friends is reported to be at The Igloo restaurant in Saskatoon at four o'clock that afternoon.
It only took three days for comparisons to be made between the disappearances of Dahrlyne and Robert and of Cathy and Samantha.
On July 31, a $10,500 reward was put forward for any information in relation to Scott and Turner.
Although there was no new information, the Saskatoon Star Phoenix published an article on Dahrlyne Cranfield, Robert Grubesic, Cathy Scott and Samantha Turner on Aug. 9, 1975, to keep their names in the press. At this point, the children had been missing for 56 and 15 days.
The case was so cold that the Saskatoon Police Service had no leads and were not getting prank calls. The reward was now $20,500 for any information related to the four children.
David Threinen, who was on a sex offenders registry, was on parole in Saskatoon at the time, unbeknownst to many — if any — in the Saskatoon Police Department in the summer of 1975.
It was not until someone informed Ken Wagner of the Saskatoon Police Service that RCMP Constables Stan Twist and Jim Kay went looking for Threinen.
On Aug. 12, 1975, 27-year-old Threinen was arrested and questioned about the disappearances. After being interviewed for eight hours, Threinen confessed and led the Saskatoon police to the two areas where Threinen tried to hide their bodies. Cathy Scott and Samantha Turner’s bodies were found northeast of the Sutherland portion of Saskatoon in a bush. Threinen then took the police to an area south of Saskatoon where Dahrlyne Cranfield and Robert Grubesic were located.
The next day, Aug. 13, the Saskatoon Star Phoenix published an article about Threinen, and about the childrens' bodies being found.
A coroner’s report released on Aug. 14, 1975, reported they died of strangulation.
Four days later on Aug. 18, 1975, Threinen was formally charged with four counts of non-capital murder, and the preliminary hearing was held on Nov. 18, 1975.
In February of 1976, Threinen’s trial was held at the Court of Queen’s Bench in Saskatoon, where Threinen pled guilty on Feb. 9. Three days later, Threinen’s psychological evaluation was released. Although Threinen was deemed not to have a psychological disorder, he was deemed to be disturbed with a history of antisocial behaviour, poor impulse control, and deemed to act out aggressively.
Threinen was found guilty and was sentenced to life in prison by Justice Edward N. Hughes on February 12, 1976.
After his sentence, Threinen bounced around to various locations such as a psychiatric centre in Vancouver and a maximum-security penitentiary in New Brunswick.
Although he was out of the spotlight for a while, Threinen was back in the headlines in 1994 because the 20th anniversary of the murders was approaching, and Threinen would be up for parole.
In July of 1995, Threinen’s parole was turned down.
He remains in custody. He is 77.