The fresco, painted in Fourth Style, shows Perseus in the act of freeing Andromeda after killing the monster to whom the young girl had been destined as a punishment. Andromeda is shown still tied to the rocks with a ring on her left wrist; her head is slightly bent to the left and her right shoulder is lowered so that the chiton, slipping down her side, leaves her right breast bare. With her right hand, she lifts the hem of her dress as she descends from the rock helped by Perseus who touches her left elbow with his right hand. The naked hero, with a chlamys and winged sandals, looks down to the left towards the sea monster lying in the water and hides the Gorgon’s head from Andromeda; the head hangs from the harpé, the curved sword that he had used to cut it off, which the hero holds in his left hand. The theme of the liberation of Andromeda by Perseus is one of the most widely depicted in antiquity: in Pompeii alone, there are six copies arranged in different compositions. This fresco, the largest to survive, seems to be the closest to the model of Nikias, the Athenian painter of the late classical period upon whose work the Roman copies are based. Nevertheless, while the older frescoes in Third Style depict a larger number of events with the presence of minor mythological characters (from Cassiopea to Cepheus), the later ones concentrate on the two most important characters, Perseus and Andromeda, foreshadowing the future sentimental relations between the two. In this fresco, despite the limitations of the amateurish pictorial technique employed, it is possible to observe the admirable attempts to rework the theme, exemplified in the accentuation of the chiaroscuro, in the softness with which the clothes are depicted and in the skilful use of light.