Luca Giordano – Mythological Scene with the Rape of Proserpine Part 6 National Gallery UK

The picture has something of this: water, people, group, underwater, ocean, swimming, fish, sea, recreation, many, seashore, mammal, swimmer, invertebrate, motion.
Perhaps it’s a painting of a group of people standing in front of a body of water with other people on the other side of the painting.