Amid the glitter and the crush of the London premiere of "Harry Potter and the Chamber of Secrets," Kenneth Branagh spotted the woman responsible for the phenomenon author J.K. Rowling.

The two had never met. But as their paths were about to cross, Branagh couldnt resist asking Rowling what she thought of his performance as the unctuous wizard, the author of Magical Me! , Gilderoy Lockhart.

"When she saw me coming, she gave me this big smile," Branagh recalled, speaking by phone from the London offices of Warner Bros. Pictures. "Rather nervously I asked her if shed liked what Id done with Gilderoy. And she said, Yes. It was fantastic. You were loathsome! "

Gilderoy Lockhart is the forever preening peacock of a wizard who arrives at Hogwarts School of Witchcraft and Wizardry (in book two) as the new Defense Against the Dark Arts teacher. He is to wizardry what Liberace was to piano playing.

He possesses a stadium-size ego, a craving for publicity that would put Madonna to shame, a flashy peacocks sense of fashion and a penchant for making grandiose claims that his skill with a wand cannot back up. Nevertheless, in the wizarding world, Gilderoy Lockhart is a media superstar whose face appears almost daily on the cover of the Daily Prophet .

When it was announced that the part had gone to Branagh, the popular reaction was, "Hes perfect." And it wasnt necessarily meant as a compliment.

"Several friends, including my sister, said the same thing: Oh my God, youre perfect. Its you. Which I found a very nerve-racking remark and response," Branagh recalled, with just a tinge of resentment.

"Its a gift of a role, though," he continued. "The combination of delicious self-obsession, the narcissism which is so full-blown as finally to be amusing thats so irritating at some point your jaw just drops in astonishment."

Then laughing, Branagh added, "Now Ive never been accused of any of those things except by my sister, and about 90 percent of the rest of the population."

It was Branaghs sister, in addition to noticing his likeness to Lockhart, who introduced him to the world of Harry Potter presenting him with a boxed set of the first three books one Christmas. It was a slow take, though, for Branagh. But like so many other Harry Potter fans around the world, once he got involved in the stories, he was hooked.

"Im very admiring of Rowling," he said. "I think its quite an achievement to lay out such a complicated adventure with all those keen observations about adolescence and school life. The books have a Dickensian quality that appeals to me very much, in terms of the characters, the detailed descriptions of costumes and atmosphere. Theyre very rich."

Branagh may have felt a hint of resentment toward those who perceived him as the incarnation of Gilderoy Lockhart. But when the offer to play the part was extended to him, he decided to pursue it.

He met with director Chris Columbus, who already had completed the filming of book one, Harry Potter and the Sorcerers Stone , and was about to embark on book two, The Chamber of Secrets .

"I dont know the full story," said Branagh. "But I do know I was not necessarily the first choice." (Several reports mentioned Hugh Grant also was being considered).

"But when I met with Chris, we got on very well," he continued. "What struck me about him was his passionate devotion to the books. Hes a real devotee with an encyclopedic knowledge of all the characters. So, when he offered me the part, I accepted."

What Columbus wanted from Branagh was a bigger-than-life performance with a colorful sense of flamboyance. But how much bigger and how flamboyant remained to be determined.

"He encouraged me to offer up a whole range of possibilities. And I can tell you that on the cutting-room floor lies a performance that was much larger than the one you see," Branagh said.

"Chris has a strong instinct for what works in the context of the overall film. And every time wed shoot a scene, he was careful to make sure there were some takes that were more naturalistic. Then hed encourage me to do dafter things.

"So, from the very beginning there were very, very florid versions along with others that were more contained. Sometimes he would say, Just go for it. Do anything you like. In the end, he went for the more contained version, which I think was right for the film."

With the release of "Harry Potter and the Sorcerers Stone" overlapping the beginning of production on "The Chamber of Secrets," the filmmakers had the satisfaction of already coming pretty close to hitting the bulls-eye. More importantly, they could relax in the knowledge that they had laid the groundwork for the films to come, such as the complex world of Hogwarts School and the dynamics of quidditch (a game like rugby played on flying broomsticks).

"I felt a tremendous consistency from Chris, a confidence about the way he wanted to tell the story," Branagh said. "I think they all felt that with the first film they had struck the right balance between what people loved about the books and what was necessary in order to make the transfer to film.

"There was a sense of relief that they had established the basic vocabulary and were now free to exploit everything in the second book that represented a development."

Ironically, a criticism that was leveled against the first film was that it remained too true to Rowlings novel. Its a criticism Branagh thinks missed the point.

"Its wonderful the way J.K. and Chris have developed a sort of hotline on any question of interpretation and detail during the course of shooting," Branagh said. "Shes not actually around the set, but shes very much a visibly active partner in the background. The films are not so much a directorial vision as a vision thats true to the work J.K. created."

Which is exactly why that thumbs up from Rowling at the opening of "Harry Potter and the Chamber of Secrets" meant so much to Branagh aka Gilderoy Lockhart.