Toward the end of “Fast Five,” the latest installment in the long-running action film franchise, characters, and by extension the characters in the film, gaze longingly at a new jet-black Dodge Challenger SRT. This at the end of a movie when those characters have raced Dodge Charger police cruisers.

Nothing too untoward there. It is, after all, a movie in which the cars are co-stars. And as product placement goes, that’s so obvious as to induce giggles. Then maybe you’ll recall the prominent role Dodges had in the February film “I Am Number 4,” from Chargers and a Challenger to even a beat-up late model Dodge pick-up.

Product placement in movies is nothing new. But filmmaker Morgan “Super Size Me” Spurlock decided to turn such brand-name pay for play into a financing scheme for his latest documentary, “The Greatest Movie Ever Sold.” The film follows him as he learns about that side of the film business, polishes his pitches and eventually lands the pomegranate juice company POM Wonderful as the major underwriter for his film.

He talks himself into a string of Mini Coopers when he lands the car company as another sponsor, and Ban deodorant, and so on.

The film stumbles as a cautionary tale of advertising saturation and manipulation, which is what Spurlock sees as a consequence of all this overt and covert advertising. He visits Ralph Nader and Noam Chomsky for predictable riffs on the evils of advertising, and Sao Paolo, Brazil, which has banned outdoor advertising (and thus looks naked, like a city in a post-apocalyptic sci-fi film). Spurlock can’t really get at whether product placement works. Did you buy a Mini Cooper because Sandra Bullock drove one in “Miss Congeniality II?” But he gets one product placer in Hollywood to tell the story of how he strong-armed a filmmaker into not using Alka-Seltzer in an unflattering and comical way in a movie.

That’s a little chilling.

Filmmakers from Bret Ratner (who naturally doesn’t see a problem with it) to J.J. Abrams (who does) weigh in.  And some of the folks who decide to sign on — the Sheetz chain of highway restaurant/convenience store/service stations — are offbeat and funny in their reasoning. There are laughs, though Spurlock seems to crack himself up more often than he does us. And POM Wonderful has already pitched in on a similar stunt, a product-placement gag by Time Magazine back in 2009.

The real public service of “Greatest Movie” is learning how these companies protect themselves in the contracts that Spurlock signs to get them on board. A Coke can is blurred out during a chat with Peter Berg (part of Spurlock’s deal with POM), Donald Trump helps explain to Spurlock how he himself is a brand, and he should exploit it. Is Spurlock “selling out” or “selling up?”

“Greatest Movie” isn’t Spurlock’s best. It plays like an overlong, overly cutesy TV news report (woman and man on street interviews included) on product placement. But if you haven’t been paying close attention to what’s being sold to you on your favorite movies, TV shows and music videos, you will after seeing this. Unless, of course, you’ve already taken a jet black Dodge Challenger for a test drive just to be like Vin Diesel.

“POM Presents: The Greatest Movie Ever Sold,” as the documentary is officially titled, opens Friday at the Regal Winter Park 20.

MPAA rating: PG-13 for some language and sexual material.

Cast: Morgan Spurlock, Donald Trump, Ralph Nader, Noam Chomsky, J.J. Abrams, many others.

Credits: Directed, co-written and produced by Morgan Spurlock. A Sony Pictures Classics release. Running time: 1:30.