Without a doubt the best of the movies for the Highlander franchise. It is clear from the movie that it is not intended for a sequel and I think that is why this is the only movie that actually make any sense.
The concept was new back in 1986 and the movie mixes past and present in a very good way, adding context and backstory to an otherwise pretty weird story of immortals cutting off each others heads for a mysterious prize.
Sean Connery is great in this movie as is Clancy Brown as the main villain.
On top of a good movie this one also comes with an amazing soundtrack by Queen.