Robert Raymond Cook was born on July 15, 1937, in Hanna, Alberta, Canada. He had a challenging early life. When he was just 9 years old, his mother passed away. This loss had a significant impact on him. He got into trouble for the first time at the age of 10 when he stole a car.

Two years later, when Robert was 12, his father remarried. His new wife was Daisy Mae Gaspar, who had been Robert's elementary school teacher. Following the marriage, the family moved from Hanna to Stettler, Alberta.

He was first jailed at the age of 14. From the time he was first incarcerated until his execution, he spent less than a year outside of prison.

On June 28, 1959, the bodies of Robert Raymond Cook's family were found in a garage in Stettler, Alberta. The victims included Robert's father, Raymond Cook, his mother, Daisy, and five children: Gerald, Patrick William, Christopher Fred, Kathy, and Linda Mae. They were all dead in their nightwear. It appeared they had been attacked while they were sleeping.

Robert Raymond Cook was arrested the day before the bodies were discovered. Police found a family car in his possession and discovered evidence connected to the family inside the trunk. When questioned about his family, Robert changed his story several times. Although he was accused of murdering the entire family, he was formally charged only with the murder of his father to expedite the legal process.

Days after the discovery of the murders, Robert escaped from a mental institution where he was held for evaluation. His escape led to a massive manhunt involving police, dogs, soldiers, and aircraft. He was eventually found hiding on a pig farm near Bashaw, Alberta.

In December 1959, Robert was found guilty of murder and sentenced to death. He had a retrial on appeal but was again found guilty in June 1960. The jury did not recommend mercy. Throughout the trial, he maintained his innocence. While on death row, he wrote a poem seeking clemency.

Finally, Robert was executed by hanging on November 15, 1960, at the Fort Saskatchewan Provincial Gaol. He was pronounced dead just after the clock struck midnight. His case remains notable in Canadian history as the last execution conducted in Alberta.