Apollo and Neptune disguised themselves as mortals and helped build the city of Troy. When Laomedon refused to pay them the agreed price the gods took revenge by bringing a series of disasters upon the city. The three are here shown consulting a plan and pointing to the city in the background. The subject derives from Ovid, 'Metamorphoses' (10).
This fresco (transferred to canvas) comes from a series painted in the Stanza di Apollo in the garden pavilion of the Villa Aldobrandini, Frascati. The execution seems to be by an assistant, although Domenichino did make four preparatory chalk drawings for the painting (Windsor, Royal Collection).