Faith begs Fred to return home, but he refuses for a reason that infuriates his wife; Bosco turns a cold shoulder to Maritza's attempts to offer her condolences; Carlos is spectacularly unsuccessful in his attempts to hit on Grace; on the day of his son's funeral, Donald Mann exacts his revenge with the help of a dirty cop by planting bombs designed to kill the police officers he holds responsible for the death of his son; after Mann's lieutenants force a man to crash a car carrying a live bomb into the funeral home where Mikey's wake is being held, Grace takes charge and goes out of protocol to save Rose's life, and Dr. Fields later swears to have her job for it; Kim's decision not to enter the funeral home while the bomb is still live stems not from cowardice, but from maternal instincts; when Mann discovers that some of his intended targets survived the bombings, he sends machine-gun wielding minions into the hospital to finish off the job.

After a fierce gun battle and some hand-to-hand combat, Mann's gunmen are finally subdued by the members of the 55 in the E.R., but not before Orland is murdered and Bosco is critically injured; after Kim heroically puts herself in the line of fire to save Holly and a little girl, she realizes that her days as a paramedic are over, and that her future lies in being a wife to Jimmy and a mother to their children; Grace and Dr. Fields patch up their differences and come to an understanding about her out-of-protocol field procedures; Maritza uncovers the traitor in their midst, who leads her to Mann; Faith steps over the line to avenge her partner.