Dermot Mulroney was received “incredibly warmly” by the Chicago Fire cast, but the same cannot be said for his character, Chief Dom Pascal.

“He's starting off pretty strong. I don't think he's there to be anyone's best friend,” Mulroney, 60, said exclusively We weekly of Pascal's appearance on Firehouse 51 during the Season 13 premiere, which airs Wednesday, September 25. “He's going to lay things out the way he thinks they should be done.”

Us previously confirmed that Mulroney was appointed as the new chief after Eamonn Walker announced in May that he would no longer be a series regular starting in season 13. (In the season 12 finale that same month, Walker's Chief Wallace Boden won the election for deputy commissioner, meaning he will no longer work at Firehouse 51.)

Mulroney's Pascal will have big shoes to fill as the new leader, the actor said Us will not be easy.

“He's a very moral guy. … That was tested a few times early in the season,” Mulroney explained, noting that Pascal, a Miami native, will be setting some “new rules for the firehouse” that not everyone will like.

He joked: “He's not there to get along with everyone. On the contrary, he's a firefighter who works on the ground.”

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Mulroney revealed that Pascal “charged into every fire incident without hesitation” when he first joined the Windy City crew, showing that “he's just as contributing to putting out a fire as anyone coming off the firehouse,” he added.

Hanako Greensmithwho plays the responsible paramedic Violet Mikami, said exclusively Us Earlier this month, she said Pascal “comes in like a stunner.” She called the new character a “little anomaly” and a “little mystery.”

Miranda Rae Mayowho plays Lieutenant Stella Kidd, agreed that Pascal is “hard to read and he's also very confident about his path forward.” She told exclusively Us that the new leader “comes and imposes his will”, but the rest of the team has “a certain pride” in the way they have always worked together.

Mulroney said that Greensmith's description of it as a “banger” was very accurate and that season 13 was “really physical” and brought more “action” to the series than he expected. “Things are bigger, louder and there are bigger explosions,” he shared.

The actor revealed that “every week is a surprise” and stressed that Pascal is a “really cool character” who will “face his own moral dilemmas” over the course of the season.

“He is truly a person who defends people, his own crew, his family,” Mulroney said Usand noted that this was the one thing he “may have in common with Boden.” However, their “bedside manner is a little different,” he joked.

Ultimately, Mulroney couldn’t have asked for a better start to the shoot Chicago Fire“It was a thrill to stumble into that cast. They really pushed me into it full throttle,” he enthused. “It was incredible.”

Season 13 of Chicago Fire Premieres Wednesday, September 25 at 9 p.m. ET.