Danny and Jackies investigation of a case involving domestic violence lead them to a high-powered city councilman. Subsequently, Danny is taken hostage after a man from his past who is bent on revenge is released from prison. Frank talks a rookie officer out of suicide and, in another instance, makes a commitment to a man to find his mothers killer. In their personal lives, Danny is concerned over Lindas new job at the hospital. Frank, meanwhile, raises questions over Henrys questionable driving and memory problems, and Erin faces off against her ex-husband in court.