The story is set in Onomichi, Hiroshima in the year 20XX. Fish disappear from the sea around the world and only whales live in the ocean. The Ministry of Fishery decides to set up giant experimental Universe Fish Tanks in space. The Onomichi Universe Fishery Union is established and begins to train space fishermen. Female fishermen are in demand due to the strengthening of an equal employment law for men and women. Six new female space fishermen are selected, and the story centers on supporting their growth.