'Chicago Fire': A Possible Change in the Firehouse Creates Friction (Exclusive Video)

THR debuts a scene from Wednesday's episode, "Ambition," which pits Lt. Casey against Mills.
"Chicago Fire"

Chicago Fire is about to get hit with internal conflict.

On the next episode of NBC's Wednesday procedural (of which the network is eyeing a spinoff), "Ambition," Mills' (Charlie Barnett) decision to join the ranks at the rescue squad is met with resentment from his firehouse colleagues -- except from Lt. Severide (Taylor Kinney).

In a scene exclusive to The Hollywood Reporter, Lt. Casey (Jesse Spencer) takes it upon himself when he sees Mills and Severide bonding by one of the fire trucks. Instead of reeling Mills in, Casey retaliates in the best way he knows how: by leaving the guy in the dust.

When Mills realizes he's been left behind, Severide reacts like a pro. But will this affect Mills' decision to join the ranks?

Is the brewing tension between Mills and Casey also connected to Dawson (Monica Raymund)?

Sometimes it's best to lay low.

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

E-mail: Philiana.Ng@thr.com
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