Zodiackillersite.com

How, if he was at a party, did the cab company or friend even get in touch with him there to ask him to cover? Would it be odd for any of them to have those numbers readily available to call and track Paul down in that manner to cover a shift? Could the other cab driver asking him to cover have been at the party with him and was too impaired to drive himself?

Makes me wonder if Z was actually at that party as well and was able to know Paul's moves prior to the killing.