The Greatest Movie Ever Sold

A movie about advertising and product placement entirely paid for by advertising and product placement? It's a Koh-i-Noor diamond of a concept, and zealous documentarian Morgan Spurlock has applied himself to his task with the efficiency of a Dyson vacuum cleaner and the tenacity of a corporate Salesman of the Month.

Spurlock, who survived a 30-day eatathon of McDonald's food despite his liver partly turning to fat and emerged with the splendid Super Size Me, has made one of the most entertaining films of the year, a far funnier one than the stuff that's routinely palmed off on us as "comedy" by the big studios. His only problem - for some critics apparently, though not your present correspondent - is whether its sheer entertainment value overshadows grave ethical questions about corporate sponsorship and the compromise of Art.

Actually, I think Spurlock (pictured right) has managed to have his cake and eat it. For one thing, Hollywood was making plenty of terrible films long before product placement was invented. For another, Spurlock's ironic tone and ability to persuade his subjects to allow him to keep the cameras rolling while he digs down to the bottom line of their commercial interests proves far more revealing than any breast-beating display of outraged rectitude would have done.

Perhaps the greatest irony is that Spurlock is a natural born salesman. If he chose to cross the line from indie provocateur to full-tilt multinational shill, he'd be awash in dollars within weeks. Early in the piece, after his first attempts to find sponsors to pony up to be in his film have failed, he lays on a bravura sales pitch to Ban deodorant, stuffed with imaginative ways the product can be displayed on screen. Then he turns the tables on Ban's marketeers and asks them what term they'd use to describe Ban's particular properties. They flounder embarrassingly for what feels like minutes, before retreating behind a smokescreen of multi-syllabled vacuity. Nonetheless, Ban come aboard because they consider themselves "a challenger brand", kind of like Spurlock is in relation to the Hollywood studios.

He has great fun with Sheetz, the Pennsylvania "Convenience Restaurant" chain, whose president is pretty sure that Spurlock is "blowing sunshine up our asses" but opts to buy in anyway. Suddenly Spurlock is conducting interviews on gas-station forecourts with big Sheetz signs looming in the background. Many laughs emanate from Spurlock's pursuit of Mane'n Tail, "the original horse-to-human crossover shampoo". He does best of all with POM Wonderful, the pomegranate drink that is said to promote prostate health, lowered cholesterol and erectile function. POM liked Spurlock's pitch so much that they came aboard as prime sponsors for a million bucks, prompting endless shots of Spurlock walking, talking or sitting with POM's distinctive "double-bulb" bottle in his hand or on the table. He does a full-scale POM commercial in a supermarket, expertly rubbishing its rival brands. The film's full official title is now POM Wonderful Presents: The Greatest Movie Ever Sold.

The instructional part is the way that Spurlock's success is also his downfall, since the more he sells, the more tightly he's bound and gagged by the contracts his sponsors force him to sign. Wading through miles of small print, he finds that he can only stay in Hyatt hotels and fly on jetBlue while making the film, may not disparage the country of Germany, has to blur out images of rival products, and has to screen the movie in advance for each sponsor.

You start to think that if this can happen to a relative minnow like Spurlock, the commercial deals that go on inside a major Hollywood release where billions are at stake must be outrageous. The next James Bond movie, for instance, will reportedly hoover up $45 millon from product placement. When Spurlock interviews movie director Peter Berg (pictured right) about the pernicious effects of product placement, Berg's righteous frustration is rendered ludicrous by the stick of Ban® deodorant sitting on the desk. More alarming is the blithe acceptance of the practice by Rush Hour director Brett Ratner ("Artistic integrity? Whatever.")

Spurlock goes to gurus like Noam Chomsky and Ralph Nader (pictured left) and frets over whether he's selling out. "Out of this film may come a transformed, corporatised Morgan Spurlock," warns Nader. "Well, have you got a pair of these?" deadpans Spurlock, whipping off his Merrell shoe and delivering a brisk sales pitch to Nader, the renowned consumer's champion. Spurlock finally decides on his alibi: "He's not selling out, he's buying in." In Hollywood or a corporate boardroom, what chance does a moral scruple stand against a slick catchphrase?

• The Greatest Movie Ever Sold is on release from Friday

Watch trailer for The Greatest Movie Ever Sold