Lindsay (Sophia Bush) and Halstead (Jesse Lee Soffer) will have each other's backs as they investigate a case guaranteed to traumatize anyone in the upcoming episode of "Chicago P.D."

In "She's Got Us," CarterMatt reports that the police will be informed of shots fired at a family residence. When Lindsay and Halstead arrive at the scene, they will discover carnage. The entire family was massacred, expect for a little girl who is clearly in shock. As the sole survivor and witness to the sad incident, the girl, the youngest daughter in the family, will have to undergo evaluation with the doctors to see if she is going to be okay. Lindsay will personally bring her to Dr. Charles (guest star Oliver Platt), but they will soon find out there is so much work to be done before she can testify.

The promo shows the hospital in chaos. The nurses rush to ask Lindsay to come to the girl's room. The officer thinks that the killer has come to finish the job, but when she cautiously scans the place, all she sees is the girl and she is holding a knife. Lindsay tries to calm her down and get her to lower the weapon. The girl looks at her with a face devoid of emotion. Will they be okay? The police will have to be very careful in treating the girl, as it is obvious she is in the brink of a nervous breakdown.

Meanwhile, Platt (Amy Morton) will be doing her best to convince Commander Crowley (guest star Barbara Eve Harris) to let Burgess (Marina Squerciati) and Roman (Brian Geraghty) remain as work partners. After the messy affair in court last episode, the precinct is in a difficult position with the higher ups. Crowley's option to put out the fire that Burgess and Roman created is to keep them as far away from each other as possible. Platt, however, thinks the move will not help the situation.

In her interview with TV Line, Squerciati talked about her ordeal last episode. She hinted that Ruzek (Patrick John Flueger) would soon know that she and Roman already slept together and his reaction would be intense. As to whether Roman was just a rebound for her character, the actress said it was unlikely, as what Burgess feels for Roman is the same emotion she once felt for her ex-fiancé.

"I don't think it's a rebound, no. I don't think it's the same feelings that she had for Ruzek. To say it's a rebound denies it the validity that it should get. Here's a person who she's in a car with for 12 hours a day and really has bonded with. He's been kind to her and supported her and would take a bullet for her. There's something very real to that. Whether it's long-lasting, I don't know," she shared.

"Chicago PD" season 3 airs Wednesdays at 10 p.m. EDT on NBC.