The unsightly, but good-natured sea god Glaucus was in love with Scylla, but this was unrequited. To win her over, he sought the help of the sorceress Circe. This was a mistake, for Circe was herself in love with him. In a fit of rage, she changed poor Scylla into a monster. Van der Neer set the story from Ovid’s Metamorphoses in sinister surroundings. Gesturing theatrically, the sorceress performs her vengeful deed.