Los Angeles  - Zombieland may rule the US box office at the moment. But the talk in Hollywood is about a real life slasher tale, where studio chiefs are being ruthlessly axed down in the corridors of power by corporate chieftains desperate to change an industry in crisis.

It's not just the global recession, changing viewing habits, and the challenge of the internet that has Hollywood on the ropes. Even the good ole days of highly paid actors starring in guaranteed blockbusters looked to be as doomed as black and white movies in the age of technicolour.

The corporate bloodletting began in June when Paramount unceremoniously ousted studio bosses John Lesher and Brad Weston. In August MGM got rid of its chief executive Harry Sloan.

Then in mid-September Disney ousted its widely revered studio chief Dick Cook. This week it was Universal's turn to act. Following a disastrous summer characterised by high profile flops such as Public Enemies, Bruno and Land of the Lost, the studio owned by General Electric canned chairmen Marc Shmuger and David Linde.

Thus in a few short months, half the major studios had a shake-up at the top.

"There's been more change in the last 18 months than in the preceding 18 years," said Mark Gill, CEO of the Film Department, an independent film finance company.

Warner, Sony and Fox have remained loyal to their leaders, but they have enjoyed far better years than the studios that ousted their head honchos. Experts say that a combination of factors now means there is less room than ever for error, or for box office flops.

Shaky film finances are at the core of the upheaval. Most significantly, DVD sales have plummeted after years in which sales of discs, coupled with the growth of overseas markets, compensated for the spiraling costs of movie-making and the anemic state of the US box office.

According to the Los Angeles Times, DVD revenue accounts for half of a film's income, with the rest split between box office receipts, television sales and merchandising tie-ins.

At the same time the global recession has made it far harder to raise capital for movie production. During the boom years wealthy individuals, hedge funds and insurance companies in the US, Germany and Japan were a key source of financing. That made it easy to pour money into risky projects, to greenlight extravagant budgets, and to turn a blind eye to wayward production values.

Those days are over, and as film companies have to put their own money on the line they want a better formula for success than the artistic intuition of studio bosses.

The effectiveness of star power also appears to be waning, says the Times' film columnist John Horn.

"Some of the town's highest-paid stars - 20-million dollar actors such as Eddie Murphy, Adam Sandler, Russell Crowe - have proved over the last year that their names on the marquee hardly guarantee that crowds will come," he wrote.

So what's the new strategy?

Disney has clearly pointed the way with the 4 billion dollar deal to buy Marvel Comics and its stable of superhero characters, and its decision to replace Cook with Rich Ross, who built Disney's cable chanel into a teenage TV powerhouse with franchises like High School Musical and Hannah Montana pointed.

"Marvel will be able to provide engaging characters without the need for highly paid stars, just like Pixar, another recent purchase did," says movie blogger David Bourne. "Ross is a proven expert at building brands and developing franchises for teenagers, who are the most important movie audience of all, especially for Disney." (dpa)