'Chicago PD' season 4 spoilers, plot rumors: Kim Burgess gets new partner; showrunner Matt Olmstead talks Brian Geraghty's replacement

A new partner for Kim Burgess (Marina Squerciati) is being sought for the upcoming fourth season of "Chicago PD." Sean Roman (Brian Geraghty), her partner as well as romantic interest in the show, decided to leave the force. Roman had been badly wounded after a shooting encounter in an earlier episode and chose to quit so he could recover fully from his injuries.

With Roman leaving, the show now has an open spot for a new character to become Burgess' partner. But it cannot be just anybody. Matt Olmstead, the "Chicago PD" showrunner, has talked about what they are looking for in this character who would soon be making a debut in "Chicago PD" season 4. The new partner would have to be someone who will have positive chemistry with Burgess so the audience would also groove on their connection.

"So we want to have someone come in who brings wind into the sails of the show ... I think we're looking for someone to come in and partner with Burgess to really re-launch that pairing of two uniforms; a robust pairing as opposed to having to carry somebody ... We want someone to come in who is already in fifth gear," Olmstead told The Hollywood Reporter.

Roman had sustained serious wounds from episode 21 of season three and was given the choice of having a desk job and less active duty or leaving the force entirely. With plans to relocate to San Diego, Roman opted for the latter, asking Burgess to go with him. Burgess, on the other hand, wanted to stay on with District 21's PD.

In reality, Geraghty, who is a producer on the show, needed to have more time to devote to his other projects. For this reason, he asked the showrunner and other producers to help him make it possible. It was Olmstead's idea to have the character Roman take a total leave of absence from the show instead of just killing him off, which has become the fallback for many character endings in the past. At the same time, Olmstead and the other show producers wanted to leave a door open for the character's return in the future should it become necessary.