Eammon Walker Eammon Walker

Is Casey a copycat or what?! Just one week after Chief Boden (Eamonn Walker) got down on one knee for his soon-to-be baby mama Donna (Melissa Ponzio) on Chicago Fire, the previews for Tuesday's season finale (10/9c, NBC) strongly suggest that Casey (Jesse Spencer) will propose to Dawson (Monica Raymund).

"You got to be happy for everybody in the house. We're a great team," Walker tells TVGuide.com with a laugh. "So there's no stealing of thunder thank you very much."

The lack of drama is refreshing considering the high emotions surrounding the chief's surprising and sudden decision to pop the question on last week's episode. "You have to take the leap of faith and what we saw Boden do last [week] was take the leap of faith with this woman," Walker says. "Maybe this woman and her energy might make it different and make him different."

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Here's hoping. The head of Firehouse 51 has already said "I do" twice before, but both unions ended in divorce. However, Boden decided to give marriage a third try when he tried to win Donna back and learned she was pregnant with his child. "He can run into a fire, he can commit to his people, he can take care of other people, but what he was really frightened of was vulnerability and this woman got through too quickly," Walker says. "It's the first time he's even been truly honest with somebody and said, 'I'm just scared.' He told the person, and how often do you get that in a relationship?"

Although Boden totally botched his first attempt at proposing in last week's episode, he course-corrected and won over Donna with a much more romantic, and traditional, second proposal. Likewise, Walker is optimistic that Boden will be able to learn from his previous mistakes as a husband. "What's great about Boden and Donna is they are a middle-aged couple. They've been in relationships before. They're not young. They are not going at it for the first time. They are not blind," he says. "So he is going to do his best to make that balance work between his firehouse and his team and his relationship."

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However, their storybook engagement won't waste time delving into serious territory, and more specifically, exploring the relationships between first responders and the significant others forced to wait by the phone to know that their loved ones are OK. "That can break up a lot of relationships and that's what he's had twice," Walker says. "You will see Fire delve deeper into what it's like for these relationships."

These relationships will be tested as soon as Tuesday's season finale when the team responds to a serious call that puts one of their own in harm's way. "The fire chief's job is to judge the fire; how much of the building is being burned before he can pull you out and therefore sacrificing whoever else is left in there, but to save who could possibly come out, and that's a big call for a chief," Walker says. "What you will see is that little moment just before he makes the decision and he's called for Severide to come out, and there's no answer."

And he's not the only one the Chief will have to worry about. "Severide is not the only one in danger," Walker adds.

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But those diehard fans hoping for any more teases beyond the season finale will have to look elsewhere. Although Chicago Fire was renewed back in March, Walker says he hasn't been able to get any information on the new season yet. "Believe me, I tried but we're all so tired after finishing Season 2, and it was a hard, hard winter in Chicago. There was a lot of snow in Chicago," he says, "so everybody's just grateful to get to the end of this. ... We need a break from each other at this point because I feel my tiredness in my bones, and I'm sure they do too."

Although Walker is looking forward to the hiatus to spend time with his family and "get some sun," he says with a laugh, it won't be long before he's clamoring to get back into action again — literally. "The 10-year-old boy in me is alive and well," Walker says. "When you're going to work and you get to drive fast cars and jump off of buildings and wear scuba gear and go under the water, it's a complete and absolute joy. Every time I put the mask on and the fire gear on and I'm sitting in a burning building ... that's a really good feeling."

Chicago Fire airs Tuesdays at 10/9c on NBC. Watch Taylor Kinney's Watchlist below: