In the episode Manhunt (2001), Fin had mentioned to John Munch that his partner took a bullet that was meant for him as to why he left Narcotics. In this episode, it is revealed that Luis Montero was the partner in question.
This is the second appearance of Cathy Moriarty (Lt Toni Howard) in the series. She previously appeared in season 6, episode 19 Intoxicated (2005) as alcoholic mother Denise Eldridge who was determined to get her underaged daughter's boyfriend charged with statutory rape only to end up dead herself.
Yul Vazquez (Luis Montero) previously played the role of Daniel Hardy in episode 11.15, Confidential (2010).