Fitz is a classic antihero, unfaithful to his wife, alcoholic, a chain smoker, overweight, addicted to gambling, manic, foul-mouthed and sarcastic, and yet cerebral and brilliant. He is a genius in his specialty: getti...展开ng into the heads of violent criminals. As Fitz confesses in "Brotherly Love": "I drink too much, I smoke too much, I gamble too much. I am too much."
Each case spanned several episodes and cliffhangers were quite often used, but it was not until the end of the second series that a cliffhanger was employed to tie off the series. Some of the plotlines in the cases took as their starting point real events such as the Hillsborough disaster, while others were purely fictional with only tangential ties to actual events.
Several different psychotic types were explored during the run of the show with increasingly complex psychological motivations that, as the series entered the middle of the second series, began to expand beyond the criminals being investigated to the regular cast members. As the series moved forward the storylines became as much about the interactions of the regulars as it was about the crimes. In many later episodes, in fact, the crimes often became background to intense, provocative explorations of the police officers' reactions to the crimes they investigated.
To emphasize how fine a line the police (and Fitz) walk in their close association with criminals, the final two series featured several stories in which the police themselves become criminals or victims of crime.