Looking for a long running series that attempts to prolong it's mystery, almost to the point of irony? Keen on an earnest depiction of upper level government bureaucracy tinged with the appeal of relatable personalities of a wunderkind paranoiac with photographic memory and a highly professional and principled woman with a large skill set? Both conveniently portrayed by charismatic actors with excellent chemistry? Then try the long running series of the X Files. Also the Lone Gunmen too, if you're still not sated.