“My action was inexcusable, but you have to punish the real culprit, and the real culprit is the one who provoked it. Voilà” — Zinédine Zidane

IT IS THE EDINBURGH FILM FESTIVAL, and Al Gore turns up for a screening of his film, An Inconvenient Truth. Another documentary about climate change is showing simultaneously — Zidane: A 21st Century Portrait, in which the ice-blood of the world’s greatest footballer suddenly boils. Disaster follows.

It is modern art does PlayerCam. A crew of more than 100 people and 17 cameras captured Zidane’s every move over the 90 minutes he played for Real Madrid against Villarreal on April 23, 2005. The film starts at kick-off and ends when Zidane leaves the pitch. Comments from the player — “I don’t see the pitch in real time” and the like — appear as subtitles.

It is directed by Philippe Parreno, a French-Algerian, and Douglas Gordon, a Turner Prize-winning artist most famous for 24-Hour Psycho, in which he stretches Hitchcock’s film so it lasts an entire day. They struck lucky with their choice of match.

Zidane was sent off right at the end for charging into a mêlée and trying to punch Quique Álvarez. Five-second psycho.

It presages the former France captain’s sending-off in the World Cup final for head-butting Marco Materazzi, the Italy defender, and shifts the film from art-house curio to mainstream asset in the bid to comprehend the 34-year-old’s motivation for the act that soured the last match of his career. Zidane said of the Villarreal incident: “I lost it for a minute, but that’s me. These things happen. That’s football.”

Why Zidane as a subject and not David Beckham, who is seen pulling Zidane away from the fight? Beckham is a celebrity, while Zidane, Gordon said, “is a Sphinx-like character. We don’t know anything about him before the game or after the game. Zidane has an astonishing charisma but is not a personality. After July 9 he’s gone underground. Apart from one Cantona-esque statement on TV, he disappeared.”

Leaving us with the strangeness of the animal act: attacking Materazzi like a bull. It is a motif visible in the film. Cameras circle Zidane, tracking him, making the Bernabéu round, like a bullring. He grunts and stares. We see him spit; we hear it, too.

Several times he drags his feet along the ground. His demeanour hints at a swelling irritation in the minutes before he is sent off, even though there is no obvious provocation and Real are leading.

It is not an Oscar-winning script. Zidane says almost nothing. “Hey, hey,” when he wants the ball. “Shameful, shameful,” he says to the referee for wrongly giving a penalty against Real.

The effect of focusing solely on Zidane is to make him seem isolated, lonely, even though he is the team’s playmaker. He jogs, walks, occasionally sprints, fouls and is fouled, crosses brilliantly to set up a goal for Ronaldo — but he remains impassive.

Gordon said: “It was bizarre sitting in a room with Zinédine Zidane looking at Zinédine Zidane saying to his image, ‘Look at you, look at you — smile! Hey, come on, say something. Say something. Show something.’ ”

The stony seriousness cracks late in the second half, when Roberto Carlos makes a joke and Zidane grins. It was, Gordon said, “the only thing in the film he didn’t like. Zidane hated it because it showed that he wasn’t concentrating on the game.” It also recalls the smile he gives Materazzi shortly before that assault.

Gordon and Zidane would walk the Bernabéu’s field. “He would point to an area on the pitch and describe something,” Gordon said. “But he wasn’t talking about his time in Madrid, he was maybe talking about his games for Juventus or Bordeaux. It was almost like the field is a flying carpet — it just moves around.”

The pitch as a space without context — does it explain why he would head-butt an opponent at such a moment on such a stage and why he would take a penalty so audaciously? Camus, another French-Algerian — and a goalkeeper — wrote L’Étranger, which translates as The Stranger or The Outsider. Both apply to Zidane, for all his fame, and this film does not solve the enigma. It adds to it. Spending an intimate 90 minutes with him at work reinforces the sense that the most brilliant footballer of his generation was — and is — the most unknowable.

“Stupidity has a knack of getting its way” — Camus

“Magic is sometimes very close to nothing at all” — Zidane

• Zidane: A 21st Century Portrait is on general release from September 29

Explore Football

• Premier League

• Football League

• Scotland

• European Football

• International Football

• TheGame

• Live Match Tracker

• The Fink Tank

• Fantasy Football