Ever since the World War II-era destroyer USS Walker was marooned on a strange alternate Earth, naturalist Courtney Bradford has been eager to fully explore the planet. Now that the war with the Alliance's enemies has settled into an uneasy peace, he is given leave to organize the Corps of Discovery, a motley company formed of veterans of the Great War from all over the Alliance. On board the rebuilt Walker, they set out to investigate reports of a region in the Pacific where ships have gone missing and a terrible bright flash of light on the horizon was witnessed. But what they find there is beyond anyone's imagination: a great battered fleet made up of strange ships. Courtney suspects the rusty armada may have been transported to this world from another, the same way the Walker was four years ago. What none of them know is that the Alliance's enemies are already aware of these lost ships - and the deadly technology they can harvest from them - and are willing to go to any lengths to steal them. Courtney, his crew of inexperienced cadets, and a handful of lethal commandos are all that stand in the way of another global war - one that the exhausted Grand Alliance simply can't win.