Threshold [http://en.wikipedia.org/wiki/Threshold_%28TV_series%29].
I only saw the 1st season, which unfortunately was all of it, but I loved it's mix of dark Sci-Fi and horror with Lovecraftian religious undertones.
What's makes it's absence even more conspicuous is that it left on a cliffhanger, there were blatantly more show written (or even made) than were broadcast before it got canned... it showed a lot of potential and obviously had the ambition to be a really epic Sci-Fi series.