Robert Raymond Cook (July 15, 1937 – November 15, 1960) was a Canadian mass murderer who was convicted of killing his father, Raymond Cook, in Stettler, Alberta, on June 25, 1959. It is alleged that Cook massacred his entire family at their home in Stettler, but was only charged with killing his father. He was found guilty of murder and sentenced to death. After officials declined to issue a reprieve, Robert was hanged in 1960. He was the last person to be executed by the province of Alberta.