Chicago PD puts its own spin on the #metoo movement. 

Ruzek and Atwater go undercover to take down a gang run by Pena, a dangerous man who was recently released from Statesville. 

According to his "posse," prison made him crazier and as part of the crew's initiation, he makes them rape and kill young women. 

They find one of the victims in an abandoned house. Burgess grabs a bracelet that was left behind and gives it to the victim's mother, who tells her the bracelet belonged to her friend, Tina. 

They find Tina at dance practice with her arm bruised, evidence she was at the house when Tina died. But since she escaped, she refuses to talk. 

Burgess feels personally invested in the case given her sister went through something similar just last year and she hasn't fully recovered. Worse? The suspect got a slap on the wrist and was due to get out of jail in roughly a year while she struggled to deal with the emotional turmoil. 

Ruzek decrypts the code, which leads them to two of the suspects, both of whom are dead with their genitalia chopped off. 

Who got to the targets before they did? It had to be someone who knew what they did and wanted revenge. 

Hank arranges a meeting with Pena through his crew, but the only thing that comes of it is more hatred for the street thug. 

"I want to break his soul," Voight tells the unit. Same Voight, same. 

They trail back to Tina since she's the only witness and thus, would want them to pay. 

She claims she didn't tell anyone, not even her boyfriend Dante as he would "think less of her."

Dante is clueless about his girlfriend's rape, but he does lead them to a third case in which a school janitor raped a girl and was later found dead with his parts mutilated. 

He adds that before the death, the janitor said a gangbanger by the name of Q threatened him. 

Turns out, Q isn't a guy, it's a girl who seeks revenge for ladies who have been victimized by castrating the suspects. 

Q refuses to confess to anything so they try to bust her on a drug run using a local gang member who delivers a backpack with "fake cocaine." Baking soda and vitamin B, if you're interested.

When the transfer happens, they chase the "runner" with the backpack through a school and realize it's Tina. 

At the station, Tina admits that after the "initiation," she called her cousin who looped in Q, saying she knew how to take care of this. 

Running the drugs was simply her way of paying back her debts.

To pop Q, they need Tina to wear a wire and force a confession out of her, which she successfully does. Unfortunately, while she's admitting to the murder she reveals her motive behind castrating — she too was raped at the young age of 14 and wanted to protect other victims. 

Despite the emotional revelation, she was still a murderer who had to be brought in. 

Q didn't crack under pressure, but she gladly agreed to help catch Pena in exchange for her girl-gang's freedom. 

Intelligence set up the meet, with Q promising to wear a wire the whole time. 

However, unexpectedly, a car pulls up and hands her a gun.

Burgess witnesses the exchange but hesitates to call it in.

Upton gives her an ultimatum — make the call or she will.

Burgess follows through but admits she wasn't 100% if it was actually a gun, so Voight disregards the warning.

When Pena arrives, Q pulls the gun on him and his men. Intelligence tries to talk her out of pulling the trigger but when Pena doubts she'll actually do it, she proves him wrong.

As Burgess is making the arrest, she scolds her for "messing up," but Q got what she wanted — Pena, the man who raped her. 

Nothing better than claiming back your power. 

After everything, Burgess comes clean to Voight about knowing it was a gun but refusing to say anything because a part of her wanted Q to take the shot and kill him.

Voight responds as if he already knows and comforts her by saying the streets of Chicago are a better place without Pena.

Then he pulls out some whiskey and tells her to "let it go."

While it was never flat-out revealed who helped Q get a gun, fans believe Voight was responsible because he too wanted Pena gone.