In the 1550s Philip II of Spain commissioned the Venetian painter Titian to create a sequence of six paintings. Given a completely free hand to choose his own subject matter for what he would call his ‘poesie’, Titian’s six paintings are credited as the greatest series of paintings in art history. But these Renaissance masterpieces – created for the collection of an ultra-pious, Inquisition-obsessed Catholic king – are not tame reliquaries. They’re instead surprisingly erotic paintings that craft a monumental beauty out of the fleeting power of lust. And their themes of love, death, passion, violence, rape and jealousy still speak powerfully to us today.