'Chicago Fire': Antonio Gives Casey a Big Ultimatum About Dawson (Exclusive Video)

Chicago Fire S03E22 Still - H 2015
Elizabeth Morris/NBC

Chicago Fire S03E22 Still - H 2015

Who's ready to rumble?

Although Chicago Fire's team at Firehouse 51 and the Chicago P.D. officers of District 21 are usually on the same side, that all changes when Antonio (Jon Seda) learns that his sister, Dawson (Monica Raymund), is trying to become the foster parent to baby Louie.

But it's not Dawson's decision to become a mom that has Antonio's blood boiling, but the fact that she's doing it solo without the involvement of her longtime beau Casey (Jesse Spencer).

In The Hollywood Reporter's exclusive video from Tuesday's new episode, Antonio storms into the firehouse to confront Casey in person and  spoiler alert  it ain't pretty.

"Why the hell is she doing this on her own?" Antonio shouts at Casey. "You were supposed to marry her. Now she's out there taking this thing on by herself."

That's not even the worst part of Dawson's brother's tirade at the man who's been "stringing her along for three years." Find out what ultimatum Antonio gives Casey in the exclusive video below:

Chicago Fire airs Tuesdays at 10 p.m. on NBC.