Dec. 11, 2001 -- Glitter, glamour and talk of tattoos — that was the order of the day at the London premiere of The Fellowship of the Rings, the first film installment of the Lord of the Rings trilogy.

When the cast reunited Monday on the steps of the Odeon Cinema in London's Leicester Square, they spoke of working on the film, based on the J.R.R. Tolkien novels, as a life-transforming event.

Young heartthrob Elijah Wood, who plays heroic hobbit Frodo Baggins in the $270 million epic, said he and eight other stars decided to get a tattoo to remember the project.

"We felt the experience was both wonderful enough and profound enough to have ourselves branded," Wood said, "so we went ahead and did that about a week before we finished."

McKellen: ‘No, I Won’t Tell You Where It Is’

About 2,000 fans gathered outside the theater for the premiere, waving posters and shouting the names of the stars. Sir Ian McKellen described playing the wizard Gandalf as "the best time I have ever had in my life."

He was among the actors who decided to commemorate the experience with a tattoo.

"When we had it done in a tattoo parlor in Wellington, New Zealand, we all swore never to tell anyone," he told Reuters Television.

You'll be able to see the film when it opens in the United States on Dec. 19, but the stars aren't really giving details yet about their new indelible marks.

Billy Boyd, who play one of Frodo's hobbit companions, Pippin, said: "To a certain extent it's kind of a little bit of a secret. Tattoos are a very personal thing we all got done to commemorate the end of the movie and you know it's kind of a little bit of a secret thing."

McKellen told reporters point-blank: "No, I won't tell you where it is."

But the British actor was much more disposed to talk about his climatic scene, when Gandalf battles a towering, flaming creature called the Balrog. McKellen says he had to imagine the whole thing in his head. There wasn't even a trace of a monster on the set. "I'm not sure how I did it because I just fought with a tennis ball on top of a stand," he said. The film and its two sequels were shot over 18 months, involving a cast of 2,400. The second and third installments will be released in 2002 and 2003.

ABCNEWS.com's Buck Wolf and ABCNEWS Radio contributed to this report.