Chapter Eight begins with Jack's return from California and his sentiment that he is no longer envious of people with secret knowledge. On his journey back to Louisiana, Jack gives a lift to a man aged 75. The man's face is immobile apart from a twitch: 'What was alive was the twitch, of which he was no longer aware.' After dropping the man off, Jack considers this twitch and wonders if the man's face knows about it. His musings become absurdist as he ponders whether only the twitch knows the 'twitch is all'. He goes on to call this the Great Twitch.
On his return home, Jack visits Willie but does not tell him that he knows of his affair with Anne.
The narrative shifts to Jack talking with Adam, and Jack asks if he can watch him perform a lobectomy. Adam agrees and Jack watches the operation with interest. After the operation, Jack does not see Adam for a while, but he is told by Anne that Adam has had a meeting with Herbert Coffee. Coffee came to see Adam to ask him to influence the Boss (Willie) in the building of the new medical center. Coffee wants the Boss to give the contract to Gummy Larson. Adam goes on to hit Coffee when he suggests there will be money in it for him if he manages to persuade the Boss.
Jack then asks Anne why she has had an affair with Willie. She replies that there was no reason not to once Jack had told her about her father's involvement with corruption. She also tells Jack that Willie wants to marry her. She says she may do later; a divorce would 'hurt him' at the present.
With Willie's acceptance, Jack manipulates Adam into taking the hospital director's job (after the conflict with Coffee) by influencing him into wanting to swear out a warrant on Coffee, and then talking him out of a court case.
There are changes in Willie's life as he and MacMurfee come into further battles. MacMurfee has discovered that Marvin Frey's daughter, Sibyl, has been a friend of Tom Stark. She is pregnant and it is likely that Tom is the father although rumours abound that she has also slept with other men. Lucy asks Jack to visit her, as she wants to know the truth about Tom. Jack tells her about Sibyl and of MacMurfee's desire to use this knowledge against Willie.
Willie decides to talk to Sibyl's father alone, but MacMurfee has moved him to an anonymous address. Willie wants the 'dirt' on Judge Irwin more urgently now as Willie believes MacMurfee would listen to the Judge. Jack agrees but firstly insists on showing the Judge his proof before involving anybody else.
At the Judge's home, Jack leads into the conversation by implying he has information on the Judge and asks him to talk to MacMurfee. He gives the Judge a day to make up his mind. When the Judge refuses, Jack refers to Littlepaugh and at first, the Judge does not even remember him. It is also mentioned that both Jack and the Judge are protecting blackmailers.
The Judge admits to the information that Jack has found and then tells him he can stop all of this, but is not explicit about what he will do.
Jack returns to his mother's home that evening and is awoken by his mother screaming that he has killed his father. It transpires that the Judge shot himself that afternoon - through the heart; therefore, the Judge is Jack's biological father.
On the day after the funeral, Jack is told that he is the main heir to the Judge's estate: 'I was the sole heir to the estate which Judge Irwin had saved, years before, by his single act of dishonesty, the act for which I, as the blameless instrument of justice, had put the pistol to his heart.'
This chapter makes its initial connections with the previous one by way of the references to the Great Twitch. In Chapter Seven, Jack ends with his nihilist 'dream' of the twitch of the nerves and this is extended with his rumination over the random twitch in the face of the man to whom he gives a lift. This demonstrates his continued adherence to contingency and shows ultimately a lack of responsibility. This view of relationships is repudiated by Jack in Chapter Ten, however.
The final pages of this chapter hold echoes of the story of Cass Mastern as Jack finally recognizes how his act of (ironic) 'blameless justice' is connected to Judge Irwin's suicide. Just as Cass understood that his affair with Annabelle led to Duncan's suicide, Jack is conscious of responsibility for his actions.
As well as being purposely laden with irony, this chapter also draws heavily on melodramatic and improbable scenes. This is not a negative criticism of these turn of events (that Jack has tried to blackmail his own father who then commits suicide). The use of melodrama is a shift from stark realism and offers the plot an exaggerated and moving turn of events. The novel makes no claims to be a realist tract; instead, it draws on high drama and coincidence to drive the narrative.