I'm watching the entire Barney Miller series from the beginning.

[Prisoner_Number_Six]

It was a great show when it started, but it seemed to lose most of its passion and real creativity by season 4, with the departure of Fish (Abe Vigoda, whom, I understand, is still alive). Right now I'm halfway through season 5, and the set seems empty- almost blank. It's become boring. Don't know if I'll be able to go to the end. I'm at the approximate point where Jack Soo passed away from esophageal cancer. That was a real loss to the world, and to the series. Barney Miller was never the same again after he left us.

A hell of a lot of great character actors visited the series- some appeared first as criminals then returned later on to become cast members and cops. Some fill-in cop characters seemed to appear and disappear quickly with no explanation. That was a real weakness in the series.

http://www.imdb.com/title/tt0072472/fullcredits#cast