Of Sea and Stars continues the saga of Interforce Agent Jess Drake and her Biological Alternative partner NM-Dev-1 that began in Melissa Good's first two books in her Partners series.
This series chronicles what happens to humankind after a massive volcanic eruption puts earth into nuclear winter. The planet is cloaked in clouds and no sun penetrates. Seas cover most of the land areas except high elevations. These exist as islands where the remaining humans have learned to make do with much less. People survive on what they can take from the sea, and with foodstuffs supplemented from an orbiting set of space stations.
This new world is divided into two factions, and the struggle for resources between them is brutal, pitting one side against the other.
In Of Sea and Stars, Jess and Dev uncover a hidden cavern at Drakes Bay full of growing vegetables and fruit trees. There is evidence that the "other side" has been negotiating with Jess's brother, and with someone on the space station that created Dev. This sends them on a quest into space to solve the mystery.