Elias Koteas' loyal but doomed detective Alvin Olinsky was murdered in prison in the show's harrowing Season 5 finale. Fans have been quite upset about it ever since, with most fans calling it the biggest blunder the show has made.
Given Al’s untimely demise, the only place fans can look forward to seeing him is in the older "Chicago P.D." episodes. While wishing Al would come back to the show probably won't make it happen, fans are always only a few clicks away from getting to see their favorite detective in action again in "Chicago P.D." reruns.