This painting depicts a scene from ancient myth. The queen of the gods, Juno, jealous of her husband Jupiter's affair with Io, changed the mortal woman into a cow. Juno then ordered Argus - a giant with many eyes - to watch over Io constantly. In response, Zeus sent Mercury, the god of deception, to free Io. Mercury lulled Argus to sleep by playing the flute, then killed him and released the cow. The artist set the scene in a landscape with classical ruins. The expansive vista belongs to an earlier tradition that evokes the immenseness of the world through panoramic views, offering the suggestion of boundless space.