During the murder trial of a notorious Russian mob boss, Erin's key witness is killed by the mobster's men, forcing Erin to turn to her only other eyewitness - a young Russian nanny. Danny and Jackie are assigned to protect the frightened girl, but after an attempt is made on her life, Danny realizes there's a mob informant on the task force and he must uncover the rat. Danny is able to discover who the informant is and at the trial the mob boss tries to intimidate the nanny by threatening her family, but with Jackie's help, the girl has the confidence to stand up and testify. Meanwhile, Mayor Poole offers Erin a position as deputy mayor, leaving Erin elated by the enormous opportunity and Frank conflicted. Caught between his job and Erin's ambitions, Frank tries to avoid the tension with his daughter until it blows up into a confrontation over the competency of the NYPD. In the end, they make up and Erin decides not to take the job because she loves the one More...she has.
