New York Undercover S04E03 - Pipeline

The unit goes after a Ukrainian kingpin who is using this "pipeline" to distribute cocaine, and causing massive deaths. But when the unit bust him, they find out that he is under diplomatic immunity and can't be prosecuted by the laws of the US. Under direct orders they are told that the case in closed. In secrecy under the order of the Chief of Detectives the unit goes undercover to shut down the "pipeline" once and for all. During the investigation, Nina considers giving up her badge if that means she can be with her daughter.