In the 1992 - 1998 syndicated TV series "Highlander," it is revealed that Duncan MacLeod (Adrian Paul) has lived nearly 400 years. He was one of many such Immortals in the world. Connor MacLeod, a family relative, came to Duncan and asked him to return to "The Game" to fight on the side of good against evil. "The Game" was the term used by Immortals to describe their hunting of one another.

When Immortals went after one another, they sought the "Quickenings". This was done by beheading (decapitating) their opponents. Duncan had been hiding from other Immortals for some time, removing himself from The Game. Now, hunted by Slan Quince, Duncan must face him. By the end of the first episode in season one, Slan was defeated. Duncan is again caught up in The Game.

While the series ran, storylines revolved around Duncan and his relationships with mortals and other Immortals. Relationships formed a theme in the series, especially Duncan's relationships with his friends, family, lovers, foes, and a secret society of mortals who call themselves 'The Watchers'. They observed, recorded but never interfered.

Because this TV series was an international hit, spin-offs occurred in the form of films (Highlander: Endgame (2000) and Highlander: The Source (2007). A spin-off TV show "Highlander: The Raven" also aired in 1998.

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