'Chicago P.D.' season 4 spoilers, plot news: Jesse Lee Soffer says Lindsay and Halstead will be 'a little more solid'

Following the events in the season 3 finale of NBC's "Chicago P.D.," viewers expect to see the members of the Chicago P.D.'s Intelligence Unit on the edge. And yet, series star Jesse Lee Soffer says that in the aftermath of Voight's (Jason Beghe) crime, his character, Intelligence Unit Detective Jay Halstead, and Halstead's girlfriend, Detective Erin Lindsay (Sophia Bush), will become closer than ever.

The season 3 finale of the police procedural drama ended with Voight murdering his son's killer, essentially giving in to his darker nature. But before he killed the man in cold blood, Voight sent Lindsay away to make sure that she doesn't get implicated in the crime. Before that, he sent his team all the way across town on a bogus tip to keep them off his tail.

As the show enters its fourth season, various questions linger. Will Voight go to prison for the murder? Is Lindsay going down with him? And how does the death of her adopted brother Justin (Josh Segarra) and the chilling murder committed by Voight, whom she considers a father figure, affect Lindsay's emotional state and her relationship with Halstead?

Speaking with The Hollywood Reporter, Soffer answered this last question, saying that in season 4, the couple, whose romantic relationship was previously a rocky one, will become closer.

"I think Lindsay and Halstead are going to be a little more solid for a bit," he explained. "They're going to enjoy being together without Voight breathing down their necks and we're going to settle down a little and see what that looks like," the actor added.

Soffer also revealed that the two may be taking things up a notch and moving in together. "It's season four, if you're going to give it a go, maybe give it a go, see what living together looks like," he said, adding, "It will be fun for the fans."

In an interview with TV Guide last month, Soffer said that Halstead will be intent on making sure that Lindsay doesn't end up in prison for Voight's crime.

"This season more than any other, Lindsay and Halstead are going to really rely on each other," he said.

"Chicago P.D." season 4 is scheduled to premiere on Wednesday, Sept. 21, at 10 p.m. EDT on NBC.