Changes are afoot at one of NBC's biggest drama franchises, with executive producers departing both Chicago Fire and Chicago P.D. for greener pastures.

Michael Brandt, co-creator of Chicago Fire, will depart the show, leaving Derek Haas as the sole showrunner, Deadline reports. The show is also losing executive producer and director Joe Chappelle. Meanwhile, Chicago P.D. executive producer and director Mark Tinker is exiting along with showrunner Matt Olmstead, whose departure was announced in March.

According to Deadline, the departing producers will likely be succeeded by existing crew members from other Dick Wolf dramas; Law & Order: SVU showrunner Rick Eid is already on tap to join Chicago P.D. for its next season.

News of Brandt, Chappelle and Tinker's departures broke less than 24 hours ahead of an NBC conference call with reporters Sunday morning, in which the network unveiled its fall schedule. Chicago Med is being bumped to midseason, and NBC has still not reached a decision on whether to renew Chicago Justice, the youngest show in the franchise.

Chicago Fire and Chicago P.D. have just been renewed for a fifth and fourth season, respectively, and will remain in their current time slots next season.

Both dramas will be airing their season finales this week.

Chicago Fire airs Tuesdays at 10/9c on NBC. Chicago P.D. airs Wednesdays at 10/9c on NBC.