I had come to learn McKee's magic formula for writing a successful screenplay. It is the get-rich-quick dream of the late 1990s: everyone's got at least one on the go, and the odds are surely better than they are with the lottery. So, if I want to be the next Nora Ephron, can McKee fix it for me?
"I pull no punches," he tells me in the break, through a cloud of cigarette smoke. "Screenwriting is the most difficult artform I know. It's complex, it takes longest to finish, and the chances of success are not great. I can't pretend anyone can be a writer. It is possible to be technically correct and emotionally empty. You also need talent, taste, intelligence, sensitivity - and then you must be able to master the artform. No, mine is not a guaranteed formula. There's no such thing." That's painful to hear, but at least honest - and extremely unusual in an industry which is flooded with flatulent promises and screenwriting guides. McKee had resisted adding to this pile - until now. Story: Structure, Style and the Principles of Screenwriting is the distillation of the seminar, and at over 400 pages, it's twice as long as any comparable guide.
"It had to be [that big] to encompass the theory. I wrote it because the time was right. I'd reached saturation point: every germane question had been asked by the students and considered by me. And," he quips, "my publishers came up with an offer I couldn't refuse."
The book is - of course! - well structured. Four sections - "The Writer and the Art of Story", "Elements of Story", "The Principles of Story Design" and "The Writer at Work" - set out the guiding principles of storytelling: setting, genre, character and meaning. There are also sections on "The Inciting Incident", "Turning Point", and "Spine", and pithy quotations, such as Ernest Hemingway's "The first draft of anything is shit."
McKee is an erudite and tough-talking iconoclast who delights in trashing films such as The English Patient and Titanic - because "They are both examples of insipid storytelling. Ninety minutes' worth of story dragged out over three hours. Titanic is a catalogue of cliches relying on spectacle. And, as for the painterly English Patient - if I had to watch that bi- plane fly over the desert one more time, I'd set myself on fire."
With the rolling hellfire wit of a New York stand-up, McKee trots out jokes and anecdotes, laced with pearls of wisdom: Plot is Character, and Character is Structure, and if your Antagonist isn't as well-observed as your Protagonist, you may as well forget it. Characters reveal their true natures at times of crisis, and it all boils down to one truth: "All a good film must do is Hook, Hold and Pay Off."
McKee knows all this because he's been there, done it. He has worked as a story analyst for NBC, a screenplay writer, and a stage actor in New York. The lifelong obsession with story structure began when he was nine years old, "when my dad made me analyse Aesop's Fables - for fun".
About 25,000 people have now done the course - half of them writers, the rest directors, actors and producers. His graduates have 17 Oscars and 91 Emmys between them. His literature is emblazoned with adulatory soundbites from John Cleese, Kirk Douglas, Faye Dunaway, Quincy Jones, Carrie Fisher and Diane Keaton.
"I mustn't bang my drum too loudly, but after Nicholas Evans took my course, he wrote The Horse Whisperer. Akiva Goldsman told me he had no career until he took my course. He went on to write a few little screenplays - such as The Client, Batman and Lost in Space."
He majors on Casablanca. "I don't say we should go back and make stories and screenplays like they did in the 1930s and 1940s," he says, as if anticipating criticism. "But those people really understood the craft of the screenplay." British movies like The Full Monty and Sliding Doors, although "charming and wonderful", don't earn the McKee imprimatur of greatness. "One is hard-pressed to find a truly great film these days. LA Confidential was very good. Shine is the most powerful father-son drama since Arthur Miller's Death of a Salesman. But they aren't great like Casablanca."
What does Casablanca offer that his whipping boy The English Patient doesn't? "Truth," he sniggers. "Truth, and a great story which grabs the audience emotionally and intellectually, takes them through time unaware, and pays them off with a great, deeply satisfying, powerful ending."
If McKee's seminar is attended on average by 150 students at pounds 300 a head, that makes pounds 45,000. Not bad motivation for three days' work, I suggest. He looks as if a skunk had just walked past. "Money? If I was only interested in money, I'd be in the automobile business like my brother."
Great screenplay writing, he is convinced, will always be unearthed. "Just show your work to any actor or director. If it is excellent, it will get made." His biggest tip is that it's a mistake to write from the outside in. "Many teachers instruct the writing of dialogue in search of scenes, the writing of scenes in search of story. I say: don't. The critical questions should be: who are these people? What do they want? How do they go about getting it?
"Writing from the inside out is how the great writers work. To be great, you must go from the inside out, and from the outside in, to be able to see what you wrote was a pile of shit. Outside in is easy. It's journalism. Inside out is painful and dangerous. But it's the only way to write something great and worthwhile."
McKee the writer has his own set of pulsating insecurities. Because, although he's sold every screenplay he's written, some twice over, written for Columbo, won a Bafta for his television "evisceration" of Citizen Kane, and will soon see his adaptation of Noel Coward's Hay Fever filmed, McKee's page-to-screen hit-rate has not been great.
He won't pretend he hasn't been disappointed. "My own work was too dark," he shrugs. In the film business, no matter how great one's expertise, lottery odds still apply.
`Story: Substance, Structure, Style and the Principles of Screenwriting' (Methuen, pounds 16.99). For details of McKee's courses, contact MediaXchange (0171 734 2310).