Vermeer's hidden cupid, the Prado's Dutch-Spanish show, plus Helen Cammock

We hear about how a painting of Cupid in one of Vermeer's greatest masterpieces, in Dresden, was long thought to have overpainted by the master himself, but was in fact covered by a later artist. It's now in the process of being revealed, as Vermeer intended. We also learn about the Prado's show where Vermeer appears alongside Velázquez and Rembrandt, among many others. And we talk to Helen Cammock about her Whitechapel show and her nomination for this year's Turner Prize.