One November evening in 1959, two men headed to the Clutter home to rob the family. Four of the six family members — Herbert and Bonnie, and their two youngest children Nancy, 16, and Kenyon, 15 — were at home asleep. The two older children — Beverly and Eveanna — were adults and didn't live in the family home at that time. The robbers went through the house to look for a safe but didn't find it. During the robbery, Herb awoke to the noise and saw what was going on. He offered the robbers all the money he had but said that it was all there was in the home, as reported by Garden City Kansas Police. Herb was known to use checks for his business dealings, so he had no need to keep large amounts of money in the house.

The thieves weren't convinced and ensued their search for the safe. In all the commotion, the rest of the family woke up. The two men believed that Herb was concealing where the safe was, and in a rage, they murdered all four family members in a gruesome manner. After the grisly deed, the men left the home with the little money that they got, as well as a transistor radio and binoculars.