CSI: NY: Season 3, Episode 21 - ProjectFreeTV

3 - 21: Past Imperfect

A serial killer whose conviction was overturned due to Mac jailing his arresting officer begins killing again, causing Mac to go after him with a vengeance. The team works on a case of a man poisoned by his brother and his brother's girlfriend with Ricin. Meanwhile, Stella gets the good news that she is HIV negative.