Does Miss Marple have to be an elderly spinster? The Agatha Christie estate is considering a younger model for the role after Geraldine McEwan laid down her knitting needles.

The actress, 75, announced her retirement as the sleuth after appearing in 12 mysteries for ITV. The Jane Marple dramas are a lucrative export, with sales to 100 countries.

ITV, with the Christie estate, is looking for a new actress to follow in the footsteps of Gracie Fields, Margaret Rutherford, Helen Hayes, Angela Lansbury and Joan Hickson.

McEwan was 70 when she accepted the role but in the competitive commercial television world, an actress below pensionable age could attract a younger audience.

An ITV spokesman said: “We will search far and wide for a new Marple. There could be a younger Marple, with actresses aged 50-plus being considered.”

Candidates for the role include Victoria Wood, 54, who won the Best Actress Bafta last year for her role in the ITV1 drama Housewife, 49. Julie Walters and Geraldine James, both 57, are also being considered.

A debate over ageism in television was fuelled by the replacement of Nick Ross, 60, as Crimewatch presenter by Kirsty Young, 39, who made her debut last night.

The Marple films are co-produced by Granada, Agatha Christie Ltd and WGBH Boston with a global audience in mind. A big name from the “ Cranford generation” of seasoned British actresses would attract viewers.

Dame Judi Dench and Dame Eileen Atkins, both 73, are expected to be approached. Prunella Scales, 75, will also be considered, as will Anna Massey, 70.

Sue Johnston, 64, who stars in Waking the Dead, could emerge as the compromise candidate to inhabit the murderous village of St Mary Mead.

Mathew Prichard, Christie’s grandson and chairman of Agatha Christie Ltd, said: “Geraldine has been a wonderful Miss Marple – the sixth actress to play her on screen in my lifetime.

“I think she brought a humanity and playfulness to the role that worked beautifully. We will miss her but are looking forward to seeing what new aspects of Jane Marple’s character our new Miss Marple might be able to explore.”

Marple appeared in in 12 novels and 20 short stories over a period of 41 years, beginning with The Murder at the Vicarage in 1930. The apparently frail woman, whose unflinching deductions from the most gruesome murder scene left local police flummoxed, soon became a favourite.

The Christie estate is owned by Chorion, an intellectual property company that has introduced the novels to a new generation through computer games and mobile platforms.

Chorion has arranged for Agatha Christie to feature in a period-set episode of Doctor Who next year; she will be played by Fenella Woolgar. An estimated two billion Christie novels have been bought.McEwan, who has filmed two final mysteries for ITV, said: “Of course, it is terribly disappointing to have to pass the baton on, but it has been a marvellous experience. I am sure that my successor will thoroughly enjoy her time with the production team.”

Case history

10 million Downloads recorded for the Death on the Nile computer game

23,000 Performances of The Mousetrap – the longest-running show in the West End

1 billion Christie books bought in Britain – and a further billion worldwide

64 Per cent share in Agatha Christie Ltd bought by Chorion in 1998

66 Novels managed by the Christie estate

154 Short stories managed by estate

100 Television dramas produced

24 Feature films produced

Source: Times database

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