Of course I did the first thing I could think of which was to go to memory-alpha.org and search for John Harrison. The closest is a recurring crewman named Harrison during the first season of TOS. Why make such a big deal about hiding the identity of the villian if he's a new character? Maybe more misdirection by Abrams the Puppeteer?
You people have ruined "Star Trek The Next Generation" for me. You are absolutely the most insufferable group of jackasses I have ever had the misfortune of spending an extended period of time with. I hope you all f@*#! die. - Stewie after spending the day with the TNG cast.