Rojas arrives at the precinct for her first day in the Intelligence unit.
She's giddy, but Platt isn't phased.
"We'll see," is Platt's attitude about any new members joining Intelligence.
On their way for a morning coffee, Atwater and Rojas come upon a carjacking in progress.
Atwater orders Rojas to call in for back-up but she fails to do so instead prioritizing her pursuit of the suspects.
One of them gets away while the other one gets impaled on a rebar during his escape.
Voight isn't pleased when he arrives on the scene and informs Rojas that it's not a good first impression.
She isn't deterred.
As Intelligence learns that the carjacking on Ruby wasn't random, they unearth a larger mystery involving Alexa, the owner of a Spanish bar who is doubling as a drug dealer.
When Ruby winds up dead, they learn that she wasn't just a bartender, she was one of the many impressionable women Alexa hired to be her drug mule.
Ruzek and Rojas go undercover. Ruzek pretends to be a drug dealer trying to get into business with Alexa after her supplier Jose Soto is arrested.
Alexa plays dumb by pretending she has no idea what he's talking about.
Rojas interjects with her plan of action -- she goes back to the bar with a fake black eye and tells Alexa that her boyfriend beat her because she butchered the deal.
Alexa is sympathetic and agrees to buy the drugs from "Maria."
Everyone is ready to arrest her at the meet, but Karla, Ruby's former roommate who blatantly lied to them, shows up.
Rojas refuses to make the deal, so Alexa backs out.
Upton and Burgess kidnap Karla and inform her that Alexa, the woman she trusts with her life, is responsible for her best friend's death.
Karla refuses to believe them, but when she realizes her other friend is also dead, she reconsiders her partnership and agrees to wear a wire.
When she confronts Alexa, the woman is thrown off but she continues to play it cool.
She hugs Karla and tells she's her favorite which is a sure sign that she's going to kill her.
Intelligence busts inside as Alexa takes Karla hostage.
With the knife pressed to Karla's throat, Alexa threatens to "cut the bitch" as Voight attempts to talk her off of a ledge.
Eventually, Alexa agrees. As she drops the knife, Karla lunges for it and stabs her in the heart.
Back at the precinct, Voight asks Upton what she thinks about Rojas.
Upton admits that she went rogue twice and didn't necessarily play as part of the team.
We then see her approach Rojas and inform her that Intelligence is a "work together" kind of unit.
Rojas seems defeated thinking she didn't pass the test, but Upton informs her that she's part of the team.
When Upton realizes that Rojas doesn't have a place to live, she tells her she can crash at her place.