A possible serial-killer case is assigned to Danny and Baez. Meanwhile, Erin considers becoming a judge; a mayoral candidate claims that Frank has been secretly investigating her spouse; and Eddie confronts her dad when he turns up in the hospital.

Erin finds out one of her informants is willing to loose his place in WITSEC to tell the truth about the true murderer of an old homicide case, the NYPD & the FDNY deal with an issue that escalades to a fight & Jamie Reagan finds help for Jenny.