One Chicago may look very different when it returns due to several cast reshuffles. NBC’s first responder/police procedural franchise is no stranger to changes in personnel. Over the years, it has seen its fair share of character exits and entrances, which have become the norm in long-running series. There are various reasons for these cast changes, but as disappointing as it is to see established characters go, it allows One Chicago to keep things fresh and interesting with fresh characters resulting in new stories to tell.

Despite being used to cast reshuffles, Chicago Fire season 11, Chicago PD season 10, and Chicago Med season 8 underwent some massive changes throughout their runs. The shows lost several key cast members due to various reasons. Meanwhile, there are certain players whose fates were left in limbo during a couple of cliffhanger finales. Simultaneously, however, other characters may be due for their return. As an ensemble, One Chicago is still able to move forward despite these changes, but it doesn’t mean that it won’t have any narrative repercussions in the upcoming seasons.

May not return:

7 Jay Halstead

Just before it returned for its 10th season, news broke out that Jesse Lee Soffer was leaving Chicago PD as Jay Halstead. As one of the few original members of Hank Voight’s Intelligence left, this was massively distressing for fans. The fact that he had just also married long-time partner and girlfriend, Hailey Upton made it worse. Chicago PD didn’t waste time tackling his exit as after only three episodes, Jay had already resigned from the force and back to his military roots for a tour of Bolivia.

Interestingly, Chicago PD kept the door open for Jay’s return, with the character promising his new wife that after eight months, he would be back in Chicago, and they would pick up where they left off. That didn’t happen, forcing Hailey to move forward with her life without a clear resolution about the status of her marriage. Considering how damaging Jay’s exit was to the show’s narrative, it’s best not to bring him back in Chicago PD season 11, especially if he has no plans of sticking around.

6 Will Halstead

Soffer’s on-screen brother, Nick Gehlfuss also decided to leave Chicago Med as Dr. Will Halstead. Admitting that it was a difficult decision, the actor explained that he thought he had done everything he could with the character. So instead of lingering, he opted for Will to finally leave. Considering how much havoc he wrecked when he left Gaffney Chicago Medical Center, it’s highly unlikely that he will just walk back to join Chicago Med season 9, even for just a cameo. In any case, he has also moved to Seattle to reconnect with Dr. Natalie Manning.

5 Ethan Choi

Before Gelfuss’ surprise Chicago Med exit, the show was already poised to lose a main character in Dr. Ethan Choi. Like Will, he was an integral element to the show’s success, eventually becoming the Chief of Emergency Medicine at Gaffney Chicago Medical Center in season 6. As a send-off, Ethan’s send-off included his much-anticipated wedding with April Sexton. The pair is supposed to stay in town, running a mobile clinic that services the underserved in the city. Despite that, there’s really no justified reason for Ethan’s return anytime soon.

4 Randall “Mouch” McHolland

Arguably the most unexpected plot in the Chicago Fire season 11 finale was Mouch getting shot while on duty. Firehouse 51 was called into a plant fire that was being intentionally set to go off as part of a domestic terrorism plan. It wasn’t until the situation was resolved that it was revealed that Mouch was shot and heavily bleeding. He got into Chicago Med right in time and was even put into a private room to recuperate, however, he ran into some complications when he started bleeding again. Chicago Fire season 11 left viewers worried if Firehouse 51’s most veteran member will survive the ordeal.

3 Adam Ruzek

The Chicago PD season 10 finale focuses on Adam Ruzek’s season-long attempt to crack into white supremacist and domestic terrorist, Richard Beck’s group. However, it was his commitment to keep Samantha Beck and her son, Callum, safe that led him to get fatally shot by the young boy. Instead of helping the injured Intelligence officer, knowing how much he had helped them, Sam decided to leave Ruzek bleeding on the floor. He was rushed to Chicago Med just in time, but it remains uncertain what his status is. Ruzek’s precarious situation has come at the worst time as he and Kim Burgess have just started to rekindle their romance.

May come back:

2 Kelly Severide

Taylor Kinney’s request for personal time off from One Chicago came at the most inconvenient time — in the middle of Chicago Fire season 11. By then, the show was setting up big things for his character and Stella Kidd as they continue to navigate being newly married. Not much has been revealed about Kinney’s situation, but the initial report claimed that his absence will just be temporary. So while he wasn’t able to return in time for the Chicago Fire season 11 finale, there are high hopes that he will finally come home to Firehouse 51 in season 12.

Narratively, Chicago Fire found a way to effectively explain Severide’s abrupt departure. Apparently, he was called to an elite OFI training camp, and considering his interest in being a fire cop, it made sense for him to prioritize that. However, his whereabouts became murky towards the end of the year, prompting Stella to travel out of town to ensure that Severide comes back.

1 Matt Casey

Jesse Spencer has officially left One Chicago, but Matt Casey has returned to Firehouse 51 several times since then. In his latest trip back home to the Windy City, he finally made the move on Sylvie Brett after his boyfriend unexpectedly broke things off with her. Casey has been clear about wanting to return to Chicago, despite Spencer’s departure from the franchise. He re-emphasizes that when he proposed to Brett.

Fans would have to wait until Chicago Fire season 12 to learn about Brett’s answer, but if she does say yes, then it will likely mean that he will stay with her in the Windy City. It doesn’t make much sense for One Chicago to revisit their relationship if they are just going to do another long-distance set-up, which was the reason for their first break-up.