Something is about to explode inside the Chicago Fire department, and it is something that firefighters can easily handle with a fire extinguisher.

In the seventh episode of "Chicago Fire" season 4 titled "Sharp Elbows," Kelly Severide (Taylor Kinney) will still be under the probation that he incurred after his previous squabble with Captain Dallas Patterson (guest star Brian White).

Incidentally, Patterson was the one who replaced Severide in his old position after he was demoted from his role as the leader of the Rescue Squad 3.

But things will change after his father (portrayed by Treat Williams) drops by to visit. Severide's dad Benny will give him several important pieces of information about Patterson, which could change his views about the person who took over his position.

Elsewhere, the fire department chief Wallace Boden (Eamonn Walker) will also have troubles of his own in this episode, after his new female neighbor (Ilfenesh Hadera) accused him of something that he never did.

Boden believes that the accusation is just a part of a frame-up, but he still has to find a way to get out of the tricky situation.

The upcoming episode will also feature the annual Chicago Fire Department Gala, where a budding romance will be seen among one of the couples inside the department.

The official synopsis for the episode reads:

"Chief Boden finds himself in the middle of a fiasco concerning a female neighbor, who he believes is setting him up. Severide, who is still on probation from his altercation with Captain Patterson, receives a surprise visit from his father and discovers some interesting information on Patterson that could be a game changer. Meanwhile, romance blossoms at the Chicago Fire Department gala."

"Chicago Fire" season 4 episode 7 airs on Tuesday, Nov 24, on NBC.