The Immortal Coltec is a Native American Hayoka — a shaman whose responsibility is to take evil into himself to protect his people. After the massacre of MacLeod's Indian family in 1872, Coltec saved MacLeod by taking in the evil and rage he felt. Since the death of his tribe, Coltec has become Hayoka to the world, protecting it from evil Immortals. But Coltec's capacity for evil isn't endless and when evil finally overtakes hin, MacLeod must find a way to save Coltec without being drawn into the evil himself.

ER trauma surgeon Anne Lindsey responds to the call for help after an explosion devastates a subway station, but when a subsequent explosion rocks the station, Anne is trapped. MacLeod remembers WWII London where he and the woman he loved, reporter Diane Terrin, were trapped in a bombed air-raid shelter during the Blitz, running out of time and air. MacLeod is desperate to rescue Anne before he loses her like he lost Diane.

World famous pianist Claudia Jarsine has a secret that even she doesn't know — she's destined to become Immortal. Immortal impresario Walter Graham, who has guided the careers of mortal greats like Shakespeare, sees his chance to shepherd Claudia's genius forever and kills her, triggering her latent Immortality — against MacLeod's better judgment. Meanwhile, Methos has fallen for Alexa, a waitress at Joe's who has a secret of her own.