So here's the story ...

The Cannes festival is the biggest film market in the world - but what makes a producer bite? Actor Peter Capaldi on the art of the pitch.

Folks with no money and a bit of an idea have always gone to folks with a bit of money and no idea and said, How about it? It's what they call "pitching". Pitching as we know it arrived in the UK somewhere between Hugh Grant stuttering through Four Weddings and Ewan McGregor putting his head down a toilet in Trainspotting. The British film industry discovered financial success was indeed possible - as long as we all went American.

And for some, it worked. Ideas were streamlined. Enthusiasm was harnessed. The director Dylan Kidd recalls giving a vigorous pitch on a conference call; after 15 minutes he was breathless. He was flummoxed by the silence at the other end, until he discovered he'd pulled the phone from the wall and had been pitching to no one.

The American film executive exists in a corporate environment as opaque and deadly as the court of the Medicis. Despite impressive displays of intelligence and savvy, they remain bewildering people. One celebrated British playwright, when pitching an Oscar Wilde biopic, was asked if he could make Bosie a girl. The head of Fox recalls that, when pitching his updated version of Romeo and Juliet, director Baz Luhrmann did not reveal until the very last moment that he intended to retain the original Elizabethan dialogue. It was said to be the worst pitch in the history of the studio. Yet they bought it, and from it sprang one of their best films.

The British can be unpredictable, too. I once pitched three ideas to the head of Britain's top film production company. He was clearly bored by ideas one and two, but on idea three he came to life. "That is a great idea," he said. "A truly great idea." I have not heard from him since.

Sometimes the American execs will decamp to London. In a grand hotel, a lady exec sat Marie Antoinette-like through my pitch without ever moving her fingers from a bowl of paper-thin potato chips. But at least she had a democratic approach to talent: as I left I saw Tom Stoppard waiting outside, along with a bloke who sold gags to the Chuckle Brothers.

Some producers will give you stock reactions, the best of which is: "I'm intrigued." Brilliant. "How did it go?" "He was intrigued!" It satisfies everyone, bestowing upon the idea a uniqueness that is hard to test, and bathing the exec in a glow of benevolent intelligence. He didn't buy it, but it haunts him.

Some truths are self-evident.

You'd better make sure you're pitching to The Guy. I'm talking bananas here.

A second, third or fourth banana might often be the only way in, but nothing happens without the say-so of the top banana. So check your banana. What's his number? Is he in the bunch? Is he actually a banana?

My worst pitch experience was in the mid-90s. The smart British film-makers were working on Jane Austen adaptations, or heart-warming comedies about redundant coalmen who regain their dignity by dressing up as women to infiltrate Women's Institute allotments and grow marijuana to fund their sons' ballet training with hilarious and moving consequences.

I, however, with my usual sure touch, was working on an updated version of the Roger Corman sci-fi shocker, The Man With the X-Ray Eyes.

The studio was the real thing. Spence, Bogey, Astaire - they'd all walked through those gates. We were early, of course. Which became on time, which became waiting.

Eventually, the guy shows up. And he is The Guy. Banana-wise, he's in the big yellow penthouse at the top of the banana-shaped Chrysler building looking down on all the other bananas, far, far below, in the streets of Bananahattan.

At that time, all studio heads were called Larry, Barry, or sometimes Gary. Larry, Barry or Gary looks like Kris Kristofferson, as rendered in wax, in a not-too-shabby country music wax museum. Fresh from Sundance, he is still roughing it in a voluminous oat-coloured cardigan and faded but very expensive denim shirt and jeans.

I launch into my pitch. It's post-Desert Storm I. Sensitive jarhead (River Phoenix or Leonardo DiCaprio or maybe David Schwimmer in a breakthrough serious role) returns home to Walton Mountain, suffering from bizarre sight problems, which eventually mutate into full-blown x-ray vision. High points included the obligatory seeing-through-the-waitress's-uniform scene (the girl from Species, I thought, in Agent Provocateur), to watching an aneurism blow in someone's brain, and eventually seeing through skin, cars, walls, buildings, mountains, the planet and universe into a new and terrifying dimension. What's not to like? Larry, Barry or Gary's eyes reveal nothing. Unlike Kris Kristofferson's, they are dead.

Keep going. As in the original, this is a journey into madness. River/Leonardo/maybe David Schwimmer in a breakthrough serious role discovers that he and his platoon have been experimented on in Iraq by the US military, which is looking to create soldier/robot hybrids. X-ray vision apparatus has been implanted into the soldiers' brains. His only choice is to track down the doctor who did the experiments and see if they can be reversed.

Not a flicker of emotion from The Guy. Now I'm feeling faint, and where his eyes are I'm seeing a cheap Roger Corman effects shot: almond-shaped card pasted over them, on to which angry flames are superimposed. I am hit with a desire of frightening power and vividness: I want to go home. Not to the hotel, not to London and my family. I want to get on a plane and go home to Scotland. To my mother. Just to be loved unconditionally.

I then heard myself say: "And we know he's in trouble because the doctor is played by Chris Walken." The eyes remained impassive, although to me they were now displaying a raging volcanic inferno. And then Larry, Barry or Gary spoke. "Chris Walken?" he said. I nodded. Without a word he got up, turned around, and walked out of the room.

The rest is a blur. I remember only blistering sunshine, lots of alcohol, and finding myself face down on the pavement, where, this being Hollywood, I was still looking up at the stars.

Of course, our film was never made. Not for the reasons you might think: some months after the pitch, the great Tim Burton announced he was doing The Man With the X-Ray Eyes for a rival studio, so all bets were off. The funny thing was, in the interim, we got the gig: a script was commissioned and we were all paid handsomely. Apparently, Larry, Barry or Garry loved it.

By Peter Capaldi in the Guardian on Wednesday May 21, 2008