The cinema special effects that are saving real lives

When some of the more squeamish filmgoers watching Danny Boyle's 127 Hours saw the scene in which James Franco amputates his arm with a blunt penknife, they fainted and suffered what breathless news reports described as "panic attacks" and "seizures" in their cinema seats.

When Jane Kleinman, who trains future doctors and nurses at Loma Linda hospital in East Los Angeles saw the exact same arm being severed, she reacted in a very different way: by deciding that the technology used to create the gruesome footage could one day end up saving lives.

Kleinman works at a facility where white-coated students use rubber dummies to simulate scenarios that might occur in a hospital emergency. But there's always been a problem with her re-enactments: the dummies, made by medical suppliers and sold to universities around the world, look more like tailor's mannequins than living, breathing human beings.

James Franco's fake arm was different, though. With its fake muscle groups, bones, tendons, and layers of skin and fat, it seemed almost indistinguishable from real flesh and blood. Spotting an opportunity to revolutionise her profession, she decided to track down the arm's creator, Tony Gardner, one of the top special effects men in Hollywood.

Months later, Gardner and Kleinman have launched a business called Simureal, which is already supplying silicone training aids to university hospitals across America. Their dummies are cheaper, and more realistic, than any that have come before. Unlikely though it sounds, technology developed to wow the popcorn-munching masses is now helping to treat sick babies.

"It's incredible for a guy like me, whose worked in film for years, to realise that the stuff we do can also affect people in the real world, in a life-or-death situation," said Gardner at his workshop in the LA suburb of Irwindale last week. "Forget whether it ever makes us money, just doing that makes this whole project worthwhile."

Gardner was standing at a wooden bench, next to a small pile of Simureal's fake, rubber babies, used during training simulations set in labour wards. In the middle of the room was a life-size model of a lion, being built from foam and clay by one of his dozen-odd employees who make props for some of the world's most watched films and TV shows. In the corner was a "fat-suit" which he made for John Travolta to wear when he played an overweight woman in the 2007 film Hairspray.

For the past 25 years, Gardner has been one of Hollywood's "go-to" guys for film-makers needing state-of-the art costumes or props. His office is an Aladdin's Cave of movie memorabilia: walls lined with posters of films he worked on, from The Addams Family (he built their house) to Jackass (he made Johnny Knoxville look like an elderly man).

Here, visitors will spot a picture of him with Gwyneth Paltrow (he built her fat-suit for the 2001 flick Shallow Hal). There, they'll see plaster casts of the faces of such film stars as Hugh Jackman, Halle Berry, and Russell Brand, who, I'm told, has one of the largest heads in show-business.

On a table is the wig that the (balding) Nicolas Cage wore in Con Air. Nearby are the space-age helmets that Daft Punk wear to conceal their identities. He's been working with the French dance music act to make the now-signature headsets since the early days of their careers.

Gardner's make-up room, meanwhile, holds the plaster cast he built to hold a crippled terrier in Something About Mary. For that movie, Gardner also crafted a silicone model of a teenager's testicles caught in the zipper of a pair of trousers. It was built at double life size, to provide sufficient detail for a famous, eye-watering close-up.

His career in special effects dates back to the early 1980s, when a chance meeting with Rick Baker, the doyen of the trade, secured him casual work on Michael Jackson's Thriller video. "I started as the guy that swept the floor, but a within a couple of weeks I was building the bladders that made it look like Jackson's face swell up," he recalls. "Then I started building zombie masks for the background dancers. In the end, I even got to be in the video. I play someone whose arm falls off."

Soon afterwards, Gardner dropped out of college and went to work for Baker full time. Among his most famous projects were building the monsters that erupt from victims' torsos in Aliens, and the mechanical toy called Chucky which turns serial killer in the Child's Play movies.

His most successful work, however, has involved recreating human cadavers and body parts. In the 1990s, after setting up his own company, Alterian, he was hired to work on the TV show ER, helping to make medical scenes look realistic. Sometimes, he says, the models ended-up looking a little bit too realistic.

"We did a lot of fake babies for that show. In fact, there was one episode when a lady gives birth in a bathroom. And the lab where the footage was developed must have thought that my fake baby was pretty lifelike, because they called the police, saying they thought we'd made some sort of snuff film. The FBI showed up at the director of ER's home the next day."

A similar incident jollified the filming of the 1999 war movie Three Kings, for which Director David Russell asked Gardner to help him shoot images that purported to show bullets travelling through the inside of a human body. So realistic were the internal organs he modelled that he was later accused of sourcing them from a real person.

"A rumour went around that we had shot a bullet through a homeless man on the streets of Phoenix, where we were filming," he recalls. "The Arizona Missing Persons Bureau, the FBI, and the Arizona police came to Warner Brothers asking questions. The day after, a mob of reporters descended on the production office."

Gardner says that such controversies make him feel "guilty, but validated as an artist." And what he does is art. His craftsmen painstakingly model intricate devices, some of them highly mechanised. And the important bit – making them look really lifelike – involves hour after hour of old-fashioned hand painting.

His profession has been revolutionised in recent years by the development of silicone rubber, which is more lifelike than the stiff, dense foam latex materials that preceded it. But trade has also been hurt by the rise of CGI film-making, where men behind computers create Avatar-style special effects.

The work Gardner did on 127 Hours was more complex than any that had come before. And with good reason: unless the amputation scene looked completely realistic, the film – about the true story of Utah hiker, Aaron Ralston, who cut his arm off after it became trapped under a rock during a climbing accident – would have failed.

He developed the fake arm over several months, trying to work out how to make realistic layers of skin, fat, muscle and tendon that would work even with extreme close-ups Eventually, 10 were built, at a cost of $10,000 (£6,200) each.

The medical training kits Gardner has since developed are cheaper, ranging in price up to $800. His firm sells a grey-coloured model baby that simulates a stillborn child. Its range also includes accessories that can be attached to dolls to simulate a range of problems which can affect living newborns, from spina bifida, to cleft palates, to infants born with intestines outside their bodies, or inside their umbilical cords.

Simureal is currently working to create mechanical model babies, which will move their limbs silently and recreate the actions of a real patient. It also sells a range of rubber masks that slot over the heads of existing dummies to help students pretend they are treating specific types of patient.

"We make an old man mask, and an old lady, and a scary guy with gangland tattoos. They all have open eyes. Nurses want to be more engaged in role play, and it helps to be realistic. You need a scary guy to actually look intimidating, so they can work out what to do when someone like that is on their ward."

Early signs are that the products are nothing if not realistic. A few weeks ago, Kleinman tried to fly home from a sales convention in New Orleans with a handful in her luggage, only to be stopped by airport security, taken into a side room, and accused of the heinous crime of attempting to transport human body parts. The allegation, quite naturally, was music to her ears.

'Seed of Chucky'

Gardner designed and built Chucky, the murderous infant's doll which stars in the long-running 'Child's Play' series of schlock-horror movies. For the fifth, and final, film in the franchise (2004), he took a cameo role as a puppeteer who is fatally strangled with piano wire. To film the scene in acceptably gory fashion, Gardner built a life-size replica of himself.

'Shallow Hal'

Gwyneth Paltrow was transformed into a 20-stone fast-food addict for this 2001 rom-com, in which her character's inner beauty helps her woo an eligible bachelor. Gardner made the transformation happen, using a 25lb fat-suit. Asked what she'd learned from the experience, Paltrow later said: "The clothes they make for women who are overweight are horrible. I felt humiliated."

'Jackass: The Movie'

He's foul mouthed. He shoplifts. He fights. He soils himself. He drives his disability scooter as if it were a Ferrari. Johnny Knoxville (aged 31 when the first film was released in 2002) was transformed into a liver-spotted old age pensioner for some of the funniest sketches in the Jackass trilogy. And Gardner did that transforming.

'The Hangover'

Ed Helms's character wakes up. He's in a Las Vegas hotel suite, the morning after the night before. A tiger is in the bathroom. A chicken is in the living room. Empty bottles are everywhere. And, to the dismay of his character, Stu Price (a mild-mannered dentist), he is missing a front tooth. Gardner's make-up for this 2009 film helped Helms and his colleagues look as if they really had been dragged through a hedge backwards.