Dermot Mulroney is leaving NBC's Chicago Fire during its upcoming 15th season, and he is not the only one: original cast member Joe Miñoso is also departing.

Mulroney, who joined the series in Season 13 as Battalion Chief Dom Pascal, confirmed the news during an appearance at the Flash Weekend Chicago Horror Convention, with his remarks reported via People and later detailed by Variety. He told the convention crowd he has one more episode left to film in Season 15, after which the writers "write the character off." His exit is expected to come early in the season, which premieres 7 October at 9 p.m. ET on NBC.

"We gave it our all for two seasons," Mulroney said of his time on the show. He described the experience warmly: "I loved every minute of it" and said he "became friends with this incredible crew of people." He added that he is "sad to see it go."

Miñoso's departure adds another layer to the shakeup. His character, firefighter Joe Cruz, will also be written off in Season 15, Variety reported. Miñoso has been with the series since it debuted in 2012, making him one of its longest-tenured cast members.

For a long-running network drama, losing two cast members at once is a meaningful shift. Chicago Fire has weathered many exits over its 13 seasons — this is a show, after all, built around a workplace where danger is the premise — but the loss of a chief and an original firefighter in the same season means the firehouse will look notably different when Season 15 opens.

Mulroney's tenure was relatively brief. Two seasons as a battalion chief is a short arc by Chicago Fire standards, where some characters have been answering calls for over a decade. His remarks suggest the exit was not his preference, though he did not indicate the circumstances behind the decision.

The writers now face the task of writing out both Pascal and Cruz. How the show handles those departures — and who steps into the gaps they leave — will be one of the storylines to watch when the new season arrives this autumn.