CSI: NY: Season 3, Episode 4

3 - 4: Hung Out to Dry

A decapitated corpse is found hung upside-down in a dorm room during a party. The shirt the victim was wearing is decorated with symbols out of numerology and Greek mythology, and also contains code words that, with the aid of a witness, leads the CSIs to a bizarre website. When another brutal murder occurs with the victim wearing a similar shirt, the team realizes they have a serial killer on their hands.