'Chicago Fire' Won't Be the Same Without [SPOILER]

*Warning: Major spoilers for Chicago Fire's Season 8 ahead*

Fans of Chicago Fire who've been committed to the show for the past seven years are still reeling from the shocking mattress factory explosion that ended with the loss of one beloved character.

If you haven't seen the episode yet, we really recommend watching and coming back here once you've wiped away the tears. No, but really, it was one of the most emotional premieres yet.

Anyway, let's get to it. What happened to Otis on Chicago Fire? Keep reading for everything you need to know.

We knew from the Season 7 finale that not everyone would make it out of the mattress fire alive, but this loss hurt more than others. 

Longtime series regular Brian "Otis" Zvonecek succumbed to the injuries he sustained during the finale and spoke his last words in Russian to Cruz, who was crying by his side.

In an interview that Derek Haas did with TV Line, he explains that he felt like one of the characters had to die in order to show the real-life perils of working in a fire department.

"I was talking to Andrea Newman and Michael Gilvary, my two head writers ... and as we were talking, we just said, 'We gotta put some teeth back into the show and we gotta show that the dangers are real," he said.

It wasn't an easy decision picking Otis to have this all happen to, however. "When we decided it was going to be Otis, there was some talk about 'Do we make it Ritter?'" Derek shared. "But it felt like that was almost not as serious ... because it wouldn't have had the stakes that it would have if it were a core cast member."

"Then we just decided it would be Otis because he lived with Cruz and Brett, and he's on Casey's truck and he's in Boden's house, and he's best friends with Mouch, and owns a bar with Hermann... There are a million feelings that everybody has from a guy who's been on the show from almost the first scene," Derek continues.

On his deathbed, Otis says something to Cruz in Russian, which we learn at the very episode means: "Brother, I will be with you always." 

As Derek tells it, that was all thanks to Arthur Forney, the head of post, who read the script in its first draft form and said, "'What if Otis said something cryptic in Russian on his deathbed and then you find out what he said was meaningful at the end?' and it was like I had been struck by lightning," Derek says.

For actor Yuriy Sardarov, the decision to move on from the show was as much his as it was the showrunners,' "We had a discussion about the character and where he was headed, and I was very upfront with [Derek] about the fact that it's been eight years, and I started when I was 22, and now I'm 31," Yuriy told Tell-Tale TV.

"I think in many ways, Otis is the one character that people don't expect to die," he continued. "It was difficult, but it was also necessary. It was a combination of me wanting to move on and them needing something akin to what's going to happen. And I think those two things met at the perfect time."

"I think it's a morbid desire of every actor to die on stage or on screen," he said. 

Watch Season 8 of Chicago Fire Wednesdays at 9 p.m. on NBC.