The transition from child star to adult performer is a difficult one, but Steve Pratt talks to three young actors who are determined not to fall by the wayside.

Bobby Driscoll's corpse, needle marks in the arm and surrounded by empty beer bottles, was discovered in an abandoned New York tenement by two children. They were probably the same age as the dead man when he was Hollywood's hottest child star. Aged just 31, he died unknown and was buried in a pauper's grave in 1968.

Nearly 40 years later, Malcolm In The Middle star Frankie Muniz is on the set of his new movie in London, North-East teenager Jamie Bell is in a car being driven back home from a photo shoot, and American actor Kieran Culkin is in England promoting his latest film.

They are three young actors with one thing in common besides talent - a desire to bridge the gap between child actor and adult performer. The hurdle has proved too much for many youngsters. Some crash and burn, caught in a downward spiral of drink and drugs. Others swiftly fade into obscurity and ordinary nine-to-five jobs. A few go on to earn a place among Hollywood's finest. But, for every Ron Howard or Jodie Foster who've made good, there's a Bobby Driscoll or River Phoenix who've failed to fulfill their promise.

The precarious nature of the profession must be apparent to Culkin who's witnessed his older brother, Macaulay, not even try to equal as an adult the success he had as the young star of the Home Alone movies. He dropped out of acting, got married (and divorced), appeared in a play on the London stage, and only recently returned to film acting.

Kieran, now 20, first appeared on screen as an eight-year-old, playing Macaulay's cousin in the first Home Alone picture. Now he's fast proving himself the better actor in films like The Mighty and new release Igby Goes Down. He's not only had to cope with the usual adolescent angst but the row, involving his father Kit's allegedly manipulative handling of his sons' careers, that split parents and children apart.

Choosing to star in Igby Goes Down, playing a rebellious teenager at odds with his dysfunctional family, is not a deliberate ploy to exorcise his demons. "That's not what I'm consciously doing. That's not why I chose to do this movie, or any movie," he says.

"As far as comparing and contrasting the film and my life, there are always basic things I can relate to. This dysfunctional family is very different to my dysfunctional family.

"I'm very proud to be a Culkin, and happy with my brother's work. I don't feel I have to break away from it. People ask what it's like to be in the shadow of him, but I don't see the shadow."

He can be thankful that child actors growing up in today's Hollywood are free from the demands of the old studio system, when desperate measures were taken to ensure their juvenile investments didn't grow up too quickly. Or, in the case of Judy Garland, not appear to grow up, to the extent that they taped down her breasts to make her look less mature as Dorothy in The Wizard Of Oz.

Some youngsters were simply discarded. Tommy Kirk was 13 when discovered by Walt Disney Studios, which put him in juvenile roles in hits such as Old Yeller, The Shaggy Dog and The Absent-Minded Professor in the late 1950s and early 1960s. His career screeched to a halt when it was discovered he was gay. He's since worked sporadically in B-movies like Blood Of Ghastly Horror and Attack Of The 60 Foot Centrefold.

Jamie Bell has, so far, resisted all attempts to be sucked into the Hollywood system, despite the praise heaped on him for his performance in Brit hit Billy Elliot, as the miner's son who takes up ballet. He enjoyed the extras such acclaim brings - going to the Oscars and mixing with names like Russell Crowe - without losing sight of the real world.

Now 17, he's making careful choices to safeguard his move into adulthood. He went back to school and took his exams rather than rushing back in front of the cameras. When he did, he opted for two very different roles - a young World War One soldier in the horror movie Deathwatch, and cripplied Smike in a new film version of Charles Dickens' classic Nicholas Nickleby. He's just returned from shooting Undertown, a low budget independent drama, in the American South.

'It's always difficult making choices," says Bell, admitting he's nervous at the task ahead. "It's not an easy job, and is always going to be hard finding the right things. I'm the kind of person who wants to do things for the right reasons, something my mother taught me from an early age. To have a long career, you have to make the right choices."

Being closely associated with a single role like Billy Elliot can be problematical, but not insurmountable as proved by American actor Henry Thomas, who's escaped the image of wide-eyed Elliott, the little lad who befriended ET in Steven Spielberg's science fiction classic, to become a player of mature roles in Legends Of The Fall and I Capture The Castle.

Frankie Muniz, who reaches 18 in December, is making the transition from child to adult roles by leading a double life. Most of the year he films as genius Malcolm, part of the dysfunctional family in popular American TV comedy show Malcolm In The Middle. During his summer holidays, he makes movies. He's currently in London filming the sequel to Agent Cody Banks, in which he plays a junior secret agent.

"I don't want to take any breaks as long as I can be on the show and do movies in between," says Muniz, who's been working for a decade after successfully auditioning for the role of Tiny Tim in a stage production of A Christmas Carol.

"I saw my sister in a play and wanted to try because it looked like lots of fun. Since I was eight, I haven't really had a time when I wasn't working," he says.

Despite his privileged position, he still views himself as a regular guy. "I'm just me, Frankie Muniz. I'm just myself, and really lucky," he says. "I went into a few auditions, got a few parts, and here I am. I know I'm not bigger or better than anyone else. I still go and hang out with my friends. I just happen to be on TV."

He seems unlikely to follow the path trod by Bobby Driscoll. At the age of six, he was earning $500 a week, a fortune in the early 1940s. He played Jim Hawkins in Disney's Treasure Island, and then provided the model and voice for the animated Peter Pan. Four years later, he was a spotty, gangly youth who couldn't get an acting job. He became a heroin addict and spent time in prison. "I was carried on a satin cushion and then dropped into the garbage can," he once observed of his less-than-charmed life.

* Igby Goes Down (15) is now showing in cinemas. Nicholas Nickleby opens on June 27, and Agent Cody Banks on July 25. Malcolm In the Middle continues on BBC2 at 6.45pm on Thursday.