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). 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. [...] Boden decided to give marriage a third try when he tried to win Donna back and learned she was pregnant with his child. What's great about Boden and Donna is they are a middle-aged couple. [...] 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. "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. 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 ...