The work begins with the description of the
town in which it is going away to commit a
crime. The author reconstructs from the day previous to the tragic event, the lives of the four people who were assassinated. They were a family of farmers very respectable in the town: workers, amiable, always arranged to help everybody, very religious,… All the town was shocked after the news, it did not exist movable pretends for this terrible crime that ended the life of four people (Hurbert, Bonnie, Nancy and Kenyon Clutter). All the country knew the happened thing, hundreds of reporters, journalists,… invaded the town breaking that tranquillity that always had surrounded to them. The
police of Kansas and also of other states dedicated itself to the investigation of this
case that by its characteristics seemed everything a mystery, not as much by the lack of tests like by unexpected and the absurd thing of the massacre. Parallelly Cape is relating the life of the assassins, as they are making those preparations to go to Holcomb in search of a
strong box, that not even they had verified that existed. The crime had been almost perfect but outside by a
prisoner, who had been companion of the penitentiary one of Dick (the brain of everything). This prisoner is the one that had to him counted that existed a family of very rich farmers in Kansas for which there was been working. From there, Dick began to be interested in like was the house in detail, the distribution of the rooms, if they had strong box, committing the error to relate to the other prisoner that when it left went to go to give a blow to the farm of the Clutter, taking with him another prisoner that was well-known, Perry, in case the case that occurred there were witnesses, of eliminating them. This prisoner was the key so that the police could follow it track of these two personages, who already almost with complete certainty had been the authors of the crime. The police continued investigating and making inquiries with the information that already they had of the prisoner, of the family of Dick, the sister of Perry, and in collaboration with the police of other states (since the assassins had been traveling from a site to another one after the crime) were able to arrest them in Fertile valleys. Both assassins had confessed their crime, counting step by step since they had planned it everything, where had hidden some tests, and since they had carried out it: when they arrived at the house, since they had not found the box strong and since later they had been tying to each victim in a room and they had given a shot them in the head.
Prisoners are condemned to capital punishment (then in Kansas it was the gift) and passed several years with consequent appeals on the part of prisoners, alleging that they did not have a right judgment, that the witnesses who were of the town and even the judge had been friends or had known the family, were executed.