CANNES, France (AP) — No place on Earth is more devoted to the "auteur" filmmaker than the Cannes Film Festival. Directors are hailed with minutes-long standing ovations, while movie stars parade a gauntlet of flashbulbs on the red carpet.

But as much as attention is lavished on the so-called "above-the-line" talent, the little guys — the below-the-line contributors on a film — are usually either unseen or totally absent. Yet one film in Cannes, "Filmworker," pays tribute to one of the hardest-working, least well-known collaborators to perhaps cinema's greatest visionary.

The film, directed by Tony Zierra, is about Leon Vitali, the longtime right-hand man to Stanley Kubrick. Despite his uncommon proximity to Kubrick and his significant contributions to the director's big-screen artistry, Vitali was — until "Filmworker" premiered — an almost entirely unsung figure in movie history.

Even more remarkable is how he came to be Kubrick's trusted assistant. Vitali was an actor with a notable and growing career whom Kubrick cast him as Lord Bullingdon, the snotty son-in-law of Ryan O'Neal's title character, in "Barry Lyndon." It was Vitali's biggest role yet — a career breakthrough — but what most interested him was learning more about Kubrick and his craft.

After spending some time in the edit suites of his next films, Vitali convinced Kubrick of his seriousness. And just like that, he more or less gave up his acting career and dedicated himself for the next two decades to working with Kubrick. He didn't leave his side until the director's death in 1999.

With slavish devotion, from morning until midnight (and often beyond), Vitali worked as a jack-of-all-trades for Kubrick. Vitali did everything from coaching actors, overseeing restorations and catering to the taskmaster filmmaker's obsessive instructions — including setting up a video monitor so that Kubrick could keep an eye on his dying cat.

"I made one truly, truly radical change in my life and that was when I said 'I'm more interested in that' than I was in the acting," Vitali said in an interview sitting outside a Cannes hotel. "That's the biggest conscious decision I've ever made. There were some sacrifices, but there were gains too."

"Filmworker," up for sale in Cannes, is an ode to the gritty, unassuming dedication of, as Zierra said, "the people in the credits" — the essential but seldom-celebrated foot soldiers of cinema. Vitali sacrificed his own fame to commit himself to helping Kubrick realize his vision — even though that often meant suffering the famously cantankerous director's nitpicking and occasional berating.

Vitali got a window into one of the movie's greatest minds and played a pivotal role in "The Shining," ''Full Metal Jacket" and "Eyes Wide Shut." (In the latter, several of the masked characters were played by Vitali.)

But the deeply humble Vitali, who had three young children, also gave up much of his life in service of Kubrick. "Full Metal Jacket" star Matthew Modine remembers him in the film as almost a "Yes, master" Igor-like figure.

"I can honestly say I've never sat there and thought: Was it worth it? I've sat there and thought there was nothing I could do about it," said Vitali. "Sometimes things aren't in your power. You're led there."

Vitali watched "Filmworker" at its Cannes premiere with his three now-grown kids by his side. When the film concluded, the theater rose to its feet and surrounded Vitali in hearty, enthusiastic applause while he smiled and nodded in gratitude. It was one of the festival's most moving moments: a minute in the spotlight for a modest "filmworker."

"I suppose I was in a little bit of a catatonic state," said Vitali. "It was wonderful to be there with my three children. Genuinely, I did not expect it would have that kind of reception."

Zierra called the moment his movie's "last scene." ''The ending," the director said, "was that night."

___

Follow AP Film Writer Jake Coyle on Twitter at: http://twitter.com/jakecoyleAP