Watch Highlander: The SeriesTV-141992|6 seasons|Sci-Fi & Fantasy,Drama,Action & AdventurePlay TrailerAdd to WatchlistTHERE CAN BE ONLY ONE.StoryDuncan MacLeod cannot die -- he is a 400-year-old immortal, who has seen his share of humanity's history. Still, he risks his life in battle against other immortals and tries to save people from harm.