Zodiac Killer: I Am the Zodiac, Pt. 2

S1 E10: He terrorized Northern California in the late 1960s, killing young couples at secluded lover's lanes. Not satisfied with just the murders, he also taunted the public with cryptic clues, threats of increased violence and most famously, ciphers that were supposed to lead police to his identity, but mostly went nowhere. Detectives, reporters, and even civilians, have worked for decades to solve the case - but so far, no one has succeeded. Can new DNA techniques that were used to catch the Golden State Killer finally unmask this murderer, who is both infamous and completely unknown?