Thirty-three seasons and 662 episodes of the One Chicago shows Chicago Fire, Chicago PD, and Chicago Med have aired since Chicago Fire premiered in 2012, and through it all, we have had to reluctantly say goodbye to many beloved characters. None of the three series’ casts look the same as they did in their respective first seasons, which is a sad but understandable truth. Most actors only stick with a show for so long before wanting to explore other opportunities. Consequently, some characters have died, while others have simply moved out of Chicago to excuse actors’ absences in the One Chicago universe.

https://screenrant.com/one-chicago-fire-pd-med-missing-characters-actors-return/