Harbinger of Darkness (The Outlier Book 1)

Free before Book 2 drops: A ragtag crew, a cynical pirate, and a commander with nothing left to lose. Arenna thought she left the military behind. Laigin thought she was looking out only for her survival in the Belt. But when a rescue mission for a missing pirate goes wrong, they uncover an alien threat to Sol System, forcing them to work together.