Interesting idea, altho' some of the leaps of intuition leading to the solution were a bit unbelievable. In the wake of a mass shooting in Washington DC, a letter is received that promises more of the same to come in short order unless a substantial ransom is paid within just a few hours. Takes place over the course of one day, New Year's Eve 1999. Surprisingly, there is absolutely no mention made of the Y2K fear that (unnecessarily, as it turned out) had everyone on tenterhooks leading up to the new millenium.
For me, the most interesting part was the information about document examination and authentication.