Christopher Innvar

While Kitty tries to find a runaway teen, Sherlock and Joan work a case in which the murder of a brilliant bioengineer looks to be at the hands of a drug cartel. Also, Joan makes a major life decision but worries it will impact Sherlock negatively, not knowing that Sherlock has big news of his own.

Alicia and Diane must constantly rethink their approach when an opposing lawyer keeps changing tactics. Meanwhile, Eli wins a victory in his efforts to protect Peter's image. Maura Tierney returns as Maddie Hayward.

While responding to a call in the field, Dawson (Monica Raymund) accidentally hits a pedestrian who stepped in front of the ambulance, and is left to deal with the repercussions. Lt. Casey (Jesse Spencer) and Lt. Severide (Taylor Kinney) disagree and continue to investigate an arson case while Chief Boden (Eamonn Walker) is left to decide whether to attend an important function in New York. Elsewhere, in hopes of preparing him for a possible promotion, Lt. Casey (Jesse Spencer) puts Herrmann (David Eigenberg) at the helm for a shift so he can discover firsthand what his superiors deal with.

After exercising his disdain and authority over Chief Boden (Eamonn Walker), Chief Anderson (guest star Michael Hanrahan) reassigns members of 51 to various houses around town, citing the need for improvement. The ramifications are felt by the crew, who are left to make the best of their respective situations in their new surroundings. Boden fights to repair the situation, but it just might be out of his control. Elsewhere, Severide (Taylor Kinney) toils over an important decision.

Elizabeth pushes for the prosecution of a diplomat after he is caught holding a maid hostage in his home. Also, Henry's father comes to visit. Emmy Award winner Tom Skerritt and Aasif Mandvi guest star. (TV-PG L, V)