Casey returns in the Chicago Fire season 10 finale trailer. With only one episode left for the year, the original Chicago series gears up for an unforgettable send-off for fans. Firehouse 51 has gone through several changes in Chicago Fire season 10, which included Lieutenant Matthew Casey's departure.

Jesse Spencer is one of the original actors in Chicago Fire, playing Casey, the Lieutenant for Truck Company 81. For a full decade, the character was a staple in the procedural, until it was announced that the Australian star is leaving the NBC show. In Chicago Fire, Casey decides to move to Portland, Oregon, so he could take care of his fallen fellow firefighter Andrew Darden's sons, who are having a difficult time with family issues. After several episodes of absence, however, Casey returns to Chicago in time for Stella Kidd and Kelly Severide's much-delayed wedding.

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The Chicago Fire season 10 finale trailer shared by TV Promos on YouTube teases what fans can expect from the much-anticipated episode titled "The Magnificent City of Chicago." Its primary focus, however, is Spencer's cameo as Casey. In the clip, he is welcomed by Boden and the rest of his former co-workers at Firehouse 51. Later on, he also has a heart-to-heart talk with his best friend, Severide, as they get ready for the actual wedding. Watch the clip below:

Click Here To See The Original Video On YouTube.

Casey's return in Chicago Fire has previously been confirmed. After all, it doesn't seem right that Kelly and Stella would get married without him back in town. It's no secret that his departure from Firehouse 51 has resulted in some massive issues in Chicago Fire, starting with the search for someone to take over his old slot. Lieutenant Jason Pelham landed the gig after impressing Chief Boden, but as Stella returned from his Girls on Fire tour, Pelham gave way for her to take over. Since Casey is already in town, perhaps as he provides Kelly some personal support in this joyous moment, he can also share some leadership tips for Stella who is settling nicely in his old professional spot.

Beyond Chicago Fire season 10, it's uncertain when Casey will be back at Firehouse 51 again. Spencer's decision to exit the NBC series stems from wanting to spend more time with his family as he moves back to Australia with them. This makes it more difficult to bring him in as frequently as fans would like to see him despite Casey being based in Portland in the show. That being said, the door continues to be open for him in case Spencer wants to more regularly revisit his role in Chicago Fire, which means that chances are, this won't be the last time viewers will see him.

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Chicago Fire airs Wednesdays on NBC.

Source: TV Promos/YouTube