Could Casey and Brett really happen? Should fans be worried about the finale? And how many boxes of tissues should we bring? Chicago Fire cocreator and showrunner Derek Haas answers all during this week’s episode of the “Watch With Us” podcast.
The original Chicago franchise returns from hiatus with a new episode on Wednesday, April 24, before taking one more week off and returning with three final episodes of the season.
“Those three are really one gigantic story. It’s going to be so fun,” Haas tells Us. “I told my wife, when I finished [writing] the finale, I said, ‘I cannot wait for them to shoot this.’”

But first, this week’s episode is focused on one hour, inside in the firehouse, when an uninvited guest (or two) comes in and wreaks havoc while a storm brews outside. While Haas didn’t want to reveal too much more about those guests, he hinted at some tension between Stella (Miranda Rae Mayo) and Severide (Taylor Kinney), which comes to a head.
“It’s definitely going to play out over these last four episodes. Particularly in this one, Kidd finds out what Foster told Severide and she doesn’t take it well,” Haas says. “While the storm is brewing outside, there’s a storm brewing inside, too.”
Later, Haas sheds light on the natural chemistry between Kinney and Mayo, something that fans can see daily on both of their Instagram accounts. “That’s how they are in real life. They’re hilarious together in a way that they’re not with other people. They just have this magic,” the writer tells Us. “I don’t think their arc is done. … The crux in which that story line hinges around has to do with Benny and we’re not done with Benny.”

However, there’s another pair that has fans raising eyebrows, too: Casey (Jesse Spencer) and Brett (Kara Killmer). Romantically, nothing has happened yet – she was best friends with his ex-wife – but they’ve grown closer throughout the season, causing fans to wonder if that’s where the story line is heading.
“I think as this season progressed and you see the two of them, and they do have natural chemistry on top of the fact that they’re kind of in the same mold, character wise,” Haas notes, adding that neither is afraid of hard work. “Overall, [they’re] really good solid people. Captain Marvel meets Captain America.”

Haas is also aware that if they do get together, not everyone will like it – and that’s OK: “Real life throws curveballs at you. Real life never goes exactly how you think it’s going to. People were like, ‘They were so in love, this doesn’t makes sense!’ I’ve known many people who were so in love and their relationship ended, and it didn’t make sense to anyone. Then you pick up the pieces and you either move on or you try to fix it.”
Listen to the entire podcast with Haas for free here, and subscribe to the “Watch With Us” podcast for more exclusive interviews.
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