C.I.D. - Season 1 Episode 677

A man’s bag, containing a diamond worth 3 crore rupees, is stolen from a train platform and CID are called to investigate. CID catch the robber but find that he has been poisoned and is dying. But to their shock- on his deathbed, the robber confesses that he knew nothing about the diamond. He was paid by someone else to rob the bag. Someone knew that there was an expensive diamond in that bag and poisoned the thief in prison to keep his mouth shut.