Some interesting trivia about John Boorman's movie Excalibur

Cinetropolis:

Boorman and collaborator Rospo Pallenberg’s script and pre-production work on Excalibur benefits from it being his fallback project after he was asked to (unsuccesfully) adapt The Lord Of The Rings for United Artists ten years earlier,
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Merlin, portrayed by Nicol Williamson, and Helen Mirren’s Morgana are very interesting characters. Neither actor wanted to work with the other, because, according to Boorman, each stated they wanted to sleep with the other on the set of Macbeth, and were rebuffed.