At any given film premiere, among those on the red carpet will be the stars, the director, producers, the scriptwriter, and studio executives. Who is the most powerful of them?
Murdoch is a Hollywood power through ownership of 20th Century Fox
Conventional wisdom holds that it is the stars, able to command multi-million dollar fees for their appearances, who have the real power.
Even the most revered directors, such as Martin Scorsese, can have difficulty in getting a film off the ground unless a big-name actor or actress is part of the package.
John Madden, who directed the Oscar-winning Shakespeare In Love, told the BBC that he found getting his latest film, Proof, into production became much easier once Gwyneth Paltrow joined the cast.
"The bigger the star you have in the movie, the more doors open for you," he said.
"It's still true, and will always remain so, that people will go and see a movie largely because of who's in it, although that becomes slightly less true at the upper, arthouse end of the market.
"Stars aren't stars for no reason. They're stars because they're extraordinary, and their presence is unusual. Their charisma is palpable, and generally speaking they're wonderful actors.
"So I've no argument with that system."
Even among actors, the playing field is not level - the most powerful stars are those who have the power to draw millions of people by their appearance in action films.
Action films are Hollywood's favoured genre, as they attract the most profitable and desirable audience, young American men.
Hollywood entertainment marketer Tony Angelotti explained that because of this, Hollywood's most powerful actor is probably Tom Cruise, whose recent films include the Mission: Impossible series, Minority Report and War Of The Worlds, while Julia Roberts "wields as much clout as any actress in Hollywood".
But another actress, Truman Show star Laura Linney, said that she felt power really lay elsewhere - in the hands of those who put up the cash for films to be made.
"I think it's the investors probably, unfortunately," she said.
But while investors provide money for individual films, corporate moguls are probably Hollywood's biggest fish - such as Summer Redstone, who controls Viacom, which owns Paramount Pictures, or Rupert Murdoch, who presides over News Corporation - who has the studio 20th Century Fox.
Mr Angelotti described Murdoch as "the guy - the supreme leader".
"These people are the supreme rulers, the way there were in the old days," he added.
"Yes they have partners, and they have to divide up their fiefdoms, but they have unbelievable power."
Beneath this elite, power resides in the players who can bring these overlords the most cash.
Prime among these are the studio executives. Their key power is the ability to "greenlight" a film - effectively taking it out of development and into production.
However, this power can have a cost. Because of the volatile nature of the industry, many executives do not stay long in their posts. And because they are the people who determine whether a film gets made, they are often unpopular with directors and screenwriters.
Terry Gilliam, the director of Brothers Grimm, Twelve Monkeys and Fear And Loathing In Las Vegas, is particularly vociferous about studio executives.
"I think the problem is most studios are run by middle management," he said.
"These are small organisations within these large multinationals, and they've got these problems of quarterly statements - they've got to keep their shares looking good.
"Nobody's thinking long-term. The people that are in there have no tenure - they're gone very quickly. So what happens is bureaucrats seem to rise through these things, and I find everybody now is like the walking dead."
A very few directors do also have, effectively, the ability to greenlight. Any project with Steven Spielberg's name attached, for example, would go straight into production.
But in most other cases, a director's power is dependent on the names in his cast.
Meanwhile, at the bottom is the screenwriter. Studio executives value star power as opposed to the storyteller - so that is where the big money goes.
Proof is Madden's (left) second collaboration with Paltrow
Terry George, who wrote and directed Hotel Rwanda, said that this made him "very uncomfortable.
"It's shifted completely the dynamic in Hollywood... if it's a Hollywood-financed film or project, the screenwriter is basically a very well-paid typist," he added.
But with revenues falling at the box office over the summer, some analysts are suggesting audiences have become bored with big special effects and want to see better stories.
If this happens, screenwriters are set to become more important.
For director Mike Mills, who recently finished shooting family drama Thumbsucker, starring Tilda Swinton and Keanu Reeves, it is ultimately too difficult to decide who has the most power.
"It's like asking who has the most power in Baghdad," he said.
"It's a constantly shifting thing. I don't think Hollywood is a big, monolithic, one-way system. There are interdependencies.
"It's like a war that's ongoing. It's not a state that's fixed."