There’s a shake-up underway at Chicago PD.

NBC’s Chicago Fire spin-off, which is set to premiere at midseason, has parted ways with leading lady Melissa Sagemiller, TVLine has learned exclusively.

Additionally, Jesse Lee Soffer — last seen on Fox’s short-lived Mob Doctor — on June 20 officially joined the cast as a series regular.

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Sagemiller’s character, CPD Detective Willhite, first appeared in Chicago Fire‘s penultimate Season 1 episode (aka Chicago PD‘s pilot).

Soffer’s character, a young police detective who grew up on the wrong side of the tracks, will be introduced on Chicago Fire via a short Season 2 arc, says Deadline.