Why did David Bowie not played Gandalf in the Lord

A little before it is completed one year from the death of David Bowie, and while we had heard about involvement with the revival of the…
Twin Peaks, we learn new things about his involvement, then, to the Lord of the Rings.
Dominic Monaghan, who plays Merry in the trilogy of Peter Jackson confirmed the rumors that were circulating a long time, stating that while he was waiting for an audition in London, he saw the Bowie into the studio. “I guess that was for Gandalf. I can’t think of anything else that would fit in the case.”
The rumors spoke of a possible involvement of the Bowie in the trilogy, with some speculation indicating that indeed he wanted to play Elrond (role ended up on Hugo Weaving). As for the role of Gandalf, he, of course went to Ian McKellen.
The director of casting for the trilogy, Amy Hubbard, replied that the Bowie was very busy. “It wasn’t available. I believe that he was there and played for everyone for the party of the Millennium. It would be new Year’s Eve of 2000, when you had the movies. He went there and entertained them all, but never did audition. That’s for sure”.
And the three movies are filmed directly, one after the other, requiring a lot of time and dedication from those who took part in the epic trilogy. The Hubbard remembers that certainly was the idea of Peter Jackson, the first two weeks, the approach of Bowie for participation in the movies.
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