So it's CSI Highlander?
Pretty much, and his nemesis is a guy who's been alive even longer... and Judd Hirsch plays his (the main lead, not the nemesis) son. They've had some really good guest stars on the show too. John Noble, Blair Brown, Jane Seymour, David Krumholtz to name a few...
I hope Netflix grabs it. AFAIK the network (ABC) actually really dug the show and liked their plan for season 2, but it pretty much just got edged out by all the new stuff coming in the fall.