A journey into the heart of one of the National Gallery of London's most famous paintings - the Arnolfini Portrait by Van Eyck.

`I've been coming to look at this for thirty years,' says one visitor, `and I don't know why it moves me so much.' Nor do the critics, nor do we.

For the last 100 years of its 500-year history, Van Eyck's secular masterpiece, a double portrait of a richly dressed couple, sometimes called `The Arnolfini Marriage', has pleased, puzzled and polarised critical and public opinion.

Radio 3 goes through the mirror into the heart of a masterpiece.

With Jack Klaff as Van Eyck.