Peter and the Wolf is a musical classic for children.
From its first performances in Stalin's Russia, its images of boy, duck, bird, cat and wolf have become a staple.
But what does Peter look like? What sort of bird is his friend? How big is the meadow? And how big is the wolf?
Pianist and entertainer Rainer Hersch is just another of those brought up on Prokofiev's tale of boyish bravery and bravado.
But he's always been troubled by the piece and how successful it is in managing that most challenging of musical tricks - painting vivid pictures.
He endeavours to find out more about the hinterland of the piece by talking, not to musicologists or musicians, but narrators.
After all, they are the people who plant the images in the minds of their young audience members.
So what are they images they have? Where is grandfather's house? How menacing is the forest home of the wolf, and how successful do they feel they are in conjuring it all up?
Alongside the likes of Richard Baker, Terry Wogan and Angela Rippon are some more unlikely figures like the American comic Peter Schikele, the broadcaster Floella Benjamin and - most telling of all - the daughter of Natalia Satz, the woman who encouraged Prokofiev to write the piece in the first place and who performed it thousands of times before handing over the role to her daughter.