CID the Oldest serial of the indian television.It is running from 1998.
I have been watching CID from 7 to 8 years.I can say sometimes it is my best time pass.One of the best thing of CID is that if you start waching it, then got attached with it and make intrest with it, so that you will not leave it till end of the serial.
They also change some characters of the serial, but the main characters like ACP Pradyuman, Senior Inspector Abhijeet, Inspector Daya, Fredricks, Dr.Salunkhe remains same from starting of the serial.That is the main thing and because of this reason we are watching and got attached with it.
Inspector Daya breaks door superbly, and the scenerio between Senior Inspector Abhijeet and Dr.Tarika is really funny.