Connor McLeod discovers in the heat of battle in the Scottish Highlands that he cannot be killed. He meets another immortal who trains him in the way of the immortals, and warns him of a battle amongst themselves to kill each other off (by beheading) until there is only one left. After watching the love of his life grow old and die, Connor wanders the earth collecting knowledge, experience, and riches, until he winds up in late 20th century New York City. It is here that the last remaining immortals have gathered to wage the final battle. While city police investigate a bizarre series of murders, Connor engages in an epic battle with his arch-nemesis to determine who will be the One.