In the new season, the operation of the Letterman Group seems to have fallen into the most difficult period. The long-term cooperation between the group and the FBI has been terminated. The new book signed by Dr. Carl Letterman (Tim Roth) has not been completed yet, and he is facing the dilemma of going to court. The relationship between this extremely talented doctor and his family and colleagues has become quite complicated. He and his daughter Emily (Hayley McFarland) are interdependent. His daughter sometimes resists her father's dominance and plays the role of a mother; his relationship with Gillian Foster (Kelli Williams) is ambiguous, testing each other, and quite tense. At the same time, various difficult cases are coming one after another, including bank robbery, theft at cultural relics exhibitions, mine explosions, religious group incidents... All of them pose the most severe and dangerous tests to Letterman.