Outwardly a scientific and exploration mission to the edge of the universe, inwardly a last-ditch effort to save humanity from itself, the mission of the Gaia is the story of the brave astronauts who undertake the voyage to colonize another galaxy.

Ryn and Josalind are caught between rival forces that would either use them, kill them, or venerate them as lost gods returned. Their best hope lies with finding the mysterious Crucible Tree. But unlocking its secrets comes with a brutal price.

Banished to the depths, a ruthless pod of merfolk are ready to take back what was once theirs by any means necessary.