Deanna Reed-Foster

The body of a 15 year old girl is found crushed in an abandoned building after she runs away from a treatment center for troubled girls. Voight (Jason Beghe) sends Halstead (Jesse Lee Soffer) undercover as a guard to work from the inside at the center, where he believes the girls are trading sexual favors for something in return. Meanwhile, Platt (Amy Morton) feels guilty because the victim was brought into the District last year, and Platt doesn't remember her.

Dawson (Monica Raymund) makes an attachment to a young boy she rescues in an apartment blaze while Kidd's (guest star Miranda Rae Mayo) big idea for Molly's turns into a disaster. Lt. Severide (Taylor Kinney) makes a pitch for the house to upgrade some of their fire masks but hits a wall in his efforts, prompting Lt. Casey (Jesse Spencer) to use his political influence to pull a few strings. Meanwhile, Cruz (Joe Minoso) and a reluctant Brett (Kara Killmer) bring in a secret weapon in their efforts to get Otis (Yuri Sardarov) to see Dr. Halstead (guest star Nick Gehlfuss) and take a blood test.

After saving a young girl, Dawson (Monica Raymund) is forced to make a tough decision when she finds out the girl's father is addicted to painkillers. Herrmann (David Eigenberg) loses his cool and gets into an altercation with a police officer after responding to a call. Otis (Yuri Sardarov) and Cruz (Joe Minoso) are on a mission to find out who Brett (Kara Killmer) is dating. Meanwhile, Boden (Eamonn Walker) is skeptical when Donna's (guest star Melissa Ponzio) brother Julian (guest star Michael Cognata) unexpectedly comes to town.

Lt. Boden (Eamonn Walker) and Jimmy (Steven R. McQueen) find themselves at odds in dealing with the aftermath of recent events while Kidd (guest star Miranda Rae Mayo) is forced to deal with her unstable and volatile ex, Grant (guest star Guy Burnet). With the help of firehouse 51, Dawson (Monica Raymund) tries to put her best foot forward in her pursuit for fostering Louie. At the urging of Susan Weller (guest star Lauren Stamile), his new political consultant, Casey (Jesse Spencer) tends to his Alderman duties and leaves town with her to attend a three-day summit. Much to his surprise, Casey embraces his new role while Susan urges him to consider grander aspirations. Meanwhile, the house responds to a dangerous structure fire that puts one of their own in a desperate situation.

A building collapses and leaves dozens of people trapped and injured; Chief Boden faces a life-or-death decision in the rescue plan; Dawson continues her quest to foster Louie; tensions flare between Casey and Antonio.