Will Shakespeare lose his beard?

To beard or not to beard, that is the question.

A portrait of William Shakespeare is set to undergo a rigorous cleaning process that could reveal that the classic image of Britain's most famous playwright could be somewhat inaccurate.

The National Portrait Gallery is mulling over doing the works on the Chandos picture for the first time in its almost 400-year history, due to advances in cleaning techniques, and could take up to a year to complete.

Painted when he was 46, it has undergone several changes, including lengthening his hair and adding in his beard, according to The Times.

Technical director of the Fine Art Restoration company, Chris Bill, said: 'The original restored works can look very different.

'You could get a dramatic revelation.'

Before the painting was bought by the Duke Of Chandos, from which it gets its name, is was owned by William Davenant, who was either his godson or illegitimate son, depending on different theories.

It became The National Portrait Gallery's first picture when it opened in 1848 after being donated by the Earl of Ellesmere.

Believed to have been painted by John Taylor, the picture is the only remaining image of him that was done from sight, with all other pictures believed to be from descriptions or memory.

The other two most famous portraits of the playwright, one by Gerard Soest and another known as the 'Chesterfield portrait', were both created after Shakespeare's death in 1616.

Art restoration expert Simon Gillespie added: 'About 30 years ago I would have said they should leave it alone.

'But today we can do very sensitive cleaning with new technology.'