Chicago Fire season 12 returned to NBC on January 17, and the opening moments revealed that Lieutenant Kelly Severide (Taylor Kinney) was back in the city after taking an extended break from Firehouse 51 to help out OFI (the Office of Fire Investigation).
But the last six months have not been plain sailing for Severide, as the episode revealed his lies has left "simmering tension" between him and wife Stella Kidd (Miranda Rae Mayo) – and his 'addiction' to working arson investigations continues to be a sore point between the pair.
Some fans have questioned whether a fourth spin-off in the One Chicago world may ever see Severide working full-time with OFI, but showrunner Andrea Newman has now told HELLO! that although they have considered the option, Severide is "too critical" to 51 to ever let him go.
"We have [considered it] but having lost Severide for a bit [in season 11,] it was a reminder of what a critical part of 51 he is," Andrea says, adding that "OFI is a great internal struggle" for Kelly which makes it a great arc for the character.
"As Kidd says early on in the episode, she considers arson as his 'drug,' and it's an addiction for him and he gets lost in it," Andrea continued.
"It's partly because it's in the blood, his dad was also in OFI, but partly because there's something that just taps into something deep within him when he gets into it. It then becomes a danger zone for him in some ways – but he also loves it and obviously has the skills for it. So that struggle will be a big part of the first few episodes of the season."
Upon his return to Firehouse 51, Stella shared her reservations about Severide becoming involved in another arson investigation and when Severide pushed back, she told him: "I basically had to fly to Alabama, put you in handcuffs, and drag you home. You get so caught up in these arson cases, it's like a drug. I didn't even know where you were in that last case, and it's taken six months for us to even try to build back any real trust."
Andrea added: "They're very much in love, obviously - it's obvious within two seconds of the premiere that they can't keep their hands to themselves! – but there's definitely a new element to this relationship and we get to see that play out and see the journey of getting through that and how that affects them."
The new season also revealed that Randall 'Mouch' McHolland (Christian Stolte) was safe and alive, while Blake Gallo (Alberto Rosende) left Firehouse 51 to live with family members he had discovered in recent months, and Christopher Hermann appeared to have been left injured after saving the team from a bomb.
"[Hermann's] big heroic save at the end of the premiere will have consequences for him both psychologically and physically – and it's going to take Darren Ritter (Daniel Kyri) with a big move to help him get past that," revealed Andrea. "Those two will end up having their relationship tested a little bit; Ritter is the one who kind of comes to save the day for Hermann."