Someone will get extra emotional in the upcoming crossover event among NBC's "Chicago P.D.," "Chicago Fire," and "Chicago Med," according to series executive producer Matt Olmstead.

The series executive producer shared a few teasers of the "Chicago" crossover episode in an interview with Entertainment Weekly, saying that the head of the "Chicago P.D." Intelligence Unit will be greatly affected in the upcoming episode.

Olmstead revealed that Chicago P.D. Intelligence Unit squad commander Hank Voight (Jason Beghe) will have a painful realization when he finds out that the doctor who allegedly kills his patients intentionally was the same one who treated his late wife.

This could mean that Voight's wife did not die because of a disease, since there is a possibility that Dr. Dean Reybold (Jeremy Shamos) killed her when she was still under his care.

"In this inaugural three-Chicago-show crossover, viewers are going to have the opportunity to see a side of Jason Beghe's Voight that they haven't experienced yet," Olmstead shared. "It's personal, emotional, and there's a good chance viewers may find a new level of compassion for him as this case brings up feelings from his past."

In the episode titled "Now I'm God," the doctor will be under investigation when four of his patients were rushed to Chicago Med after being overdosed with their chemotherapy treatment. Lindsey (Sophia Bush) and Halstead (Jesse Lee Soffer) tried to gain access to the doctor's medical files, but he initially refused to give them until the court gave them a warrant. Upon checking, the investigators of Chicago P.D. will realized that all of the doctor's patients were being poisoned from using unnecessary chemo.

The three-episode crossover will start with an episode in "Chicago Fire" and "Chicago Med" on Tuesday, Jan.5, while the big conclusion will air on Wednesday, Jan. 6, on NBC.