Jack wakes up drunk in the city, and realizes he needs to get out, and fast. He makes his way to Monsanto's cabin.
Jack returns to Big Sur two more times before the novel's climax. In the meantime he meets up with his old friends, (Cody included), and begins a messy love affair with Billie. Act II ends at the peak of Jack's madness, Chapter Thirty-Seven.
Jack recovers from his madness by simply falling asleep. He ends his novel on a surprisingly optimistic note, though whether or not anything has been resolved is subject to debate.