CSI: NY Episode 6.02 Blacklist (Featuring Gravedigger)

Mac realizes two seemingly unconnected murders were done remotely by the same sophisticated hacker. Mac then discovers the murderer has been monitoring the murders and he observes Mac working on the case. Things get really personal when he calls Mac, taunting him. Mac figures out the murderer is killing the people responsible for cancelling his cancer treatment because he lost his job and health insurance; he's dying and is taking his anger out on others. The killer assumes Mac will understand because Mac's father died of cancer, but in flashback, we learn that Mac's father handled his dying with dignitiy and grace, encouraging Mac to move to New York to start his own life. They finally catch the killer as he goes after his third victim.