Stars who went too far for movie roles

We heard today that Rooney Mara (gasp!) had her nipple pierced for her role as Lisbeth Salander in the upcoming ‘The girl With the Dragon Tattoo’.

[See more: 'The Girl with the Dragon Tattoo' review]

While somewhat impressive, this is nowhere near the level of dedication shown by some (clearly mad) actors. The nuttiest ways stars got into character have included…

…paying a doctor to mangle their teeth

Robert De Niro is famous for piling on the pounds to play a fat Jake LaMotta in Raging Bull, but we reckon forking out $20,000 for a doctor to grind down his teeth for ‘Cape Fear’ is even more remarkable/mad. He wanted to look more menacing.

… assuming the personality of Andy Kaufman

Plenty of stars stay in character throughout movie shoots, but Jim Carrey went the extra mile for ‘The Man in the Moon’. He took on the personality of Andy Kaufman for months on end, refusing to acknowledge that he wasn’t the nutty comedian. He apparently annoyed co-workers and his girlfriend with constant (obviously annoying) practical jokes.

[See more: Biggest movie flops of 2011]

…eating a live cockroach

The most infamous scene in 1989 flick ‘Vampire's Kiss' is when Nicolas Cage chases a cockroach round his flat, before eating it live. Speaking about the scene, he once said: "To this day, people ask me about the cockroach - it was disgusting…. I have a fear of bugs and I had to disinfect my mouth with 100-proof vodka and just spit the bug out.” 

…selling all their possessions

Adrien Brody is another method specialist, as seen in the build-up to holocaust Oscar-winner ‘The Pianist’. Before filming he sold all his possessions, including a New York flat, car and mobile phone, to get into the mindset of a polish Jew who’d lost everything to the Nazis. He won an Oscar for his troubles.

[See more: Incredible behind-the-scenes footage from 'Rise of the Planet of the Apes']

…being knocked out by a real boxer

Sylvester Stallone, 60 when filming ‘Rocky Balboa’, wanted the fight scenes to be realistic - unlike the heavily choreographed bouts in the previous films. So he had villain Mason ‘The Line’ Dixon punch for real during shooting. The problem; Mason was played by really-life boxing star Antonio Tarver and he knocked Sly out cold during the shoot.

…burning their flesh with real hot wire

That scene in ‘Oldboy’, when Min-sik Choi uses hot wire to burn his flesh to mark how many years he’d spent in prison… he did that FOR REAL and it was captured on camera. He also ate a live octopus.

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...breaking their ribs from being hunched in a wheel-chair

Daniel Day-Lewis takes all his roles seriously - he trained for 18 months with Barry McGuigan for 'The Boxer' and took up an apprenticeship as a butcher for ‘Gangs of New York' – but really pushed the boat out for ‘My Left Foot’. Playing paralysed poet Christie Brown, he refused to leave his wheelchair between scenes and BROKE TWO RIBS by sitting continually hunched for months on end. Nutter.