Members of the fire and rescue squads become hostages when a group of armed gang members invades and assumes control over Firehouse 51 during a turf war.
A series of similar car accidents raises suspicion that someone may be targeting innocent people; Severide tries to make Anna feel welcome in her new Chicago surroundings; a persistent constituent asks for Alderman Casey's help in resolving an issue.
Murdoch and Crabtree enjoy a war re-enactment, until a fellow pretend soldier is murdered.
In 1981, police are shocked by the violent murder of a 35-year-old woman inside her home in an affluent town.
After a multi-millionaire is shot in his own mansion and eventually succumbs to his wounds, it takes years until a family friend implicates the true mastermind behind the deadly plan.
Intelligence's investigation of a nightclub owner suspected of cocaine distribution is complicated when Ruzek recognizes someone close to him while working undercover.