When a child actor is cast as the grubby urchin Oliver it can prove a ticket to stardom or a curse. So the BBC has ruled that Andrew Lloyd Webber, not viewers, will make the final decision in its latest West End talent search.

After solving a problem like Maria and discovering a Joseph fit to wear a dreamcoat, the BBC One Saturday night series I’d Do Anything will find new stars for Sir Cameron Mackintosh’s revival of Oliver!

Thousands of young hopefuls have auditioned for the lead role in Lionel Bart’s classic musical, with Lord Lloyd-Webber demanding an Oliver who can demonstrate “grit and steel”.

The most famous Oliver, Mark Lester, shot to stardom aged 9 when he was cast in the 1968 film. But he succumbed to drink and drug abuse and his film career dried up. Lester forged a new career as an osteopath.

The BBC is keen to avoid accusations of exploiting child actors. Lord Lloyd-Webber will choose three Olivers in consultation with an expert jury including Barry Humphries, who starred as Fagin in Sir Cameron’s previous London staging.

A BBC spokesman said: “Oliver is played by a minor so the role will not be open to the public vote. This decision was taken in the best interest of the children following expert advice.” The BBC is required to “protect the welfare” of children who appear in shows at all times.

Viewers will instead be asked to select an actress to play Nancy, Oliver’s co-star, who sings many of the most famous songs and must be aged over 17. Lord Lloyd-Webber is seeking a “streetwise Nancy – a sort of Amy Winehouse”. The producers admit they are seeking girls from as “many different backgrounds and ethnic groups” for the role.

MPs complained the BBC’s hit talent shows gave “undue prominence” to the West End shows that follow.

On this occasion, Sir Cameron has not been given a role as judge on I’d Do Anything but he will appear to discuss the cast with Lord Lloyd-Webber. The peer has no financial interest in the subsequent West End production.

Connie Fisher, 24, winner of the Maria search, enjoyed a sell-out run in The Sound of Music. But a forthcoming concert tour has been cancelled amid reports of poor ticket sales.

The BBC said 14p from each phone vote will go to the BBC Performing Arts Fund, which gives bursaries to aspiring performers and musicians. I’d Do Anything, presented by Graham Norton, is on BBC One on Saturday.

What happened next

— John Howard Davies (Oliver in David Lean’s 1948 film) was BBC head of comedy from 1977 to 1982

— Anthony Newley (Lean’s Artful Dodger) was an actor, composer and Joan Collins’s former husband

— Mark Lester (Lionel Bart’s Oliver in 1968) an osteopath hoping to return to the screen

— Jack Wild (Bart’s Artful Dodger) pop singer and children’s television star before alcoholism and cancer claimed him

— Phil Collins (Dodger in 1964) achieved global success with the band Genesis and in his solo career

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