The zodiac killer is still out there.
Actually, probably not. There’s a decent chance he died of diabetes in 1992.
Or, he may have become the unabomber.
There's even been talk that he ran for president in this last cycle.
The point is, in the absence of definitive answers, everyone’s a suspect. Because of that, a nice little cottage industry has been created, along with a masterpiece movie and another excellent one.
The real question is: can you account for your whereabouts on the nights of December 20 1968, July 4 1969, September 29 1969 and October 11, 1969?
No? You're a f*#king suspect.