In Book 2 the Lost Fleet is advancing deeper into Syndic Space and is having a major Battle in one of the major Syndic Shipyard System.
There is alot of reasoning around the Hypernet portal, which the Syndic sabotage as a last stand in battle.
Due to the unkown origin of the portal and their way to operate the Allies start to wonder who build them and gave them to the human race. Theres a very light hint about the possibility of non human existance, a fact that seems highly impossible in the Universe of the Lost Fleet.

Please note that i am intendetly not describing the main plot of the book (Captain Falco's treason etc); as i am leaving that to you. My review should only indicates the general direction of the complete Lost Fleet compendium.

On a personal note, i am very pleased that the story doesnt lose in its momentum and on certain episodes even accelerates.
Generally, the Lost Fleet has the potential to become my favorite Sci-Fi Saga.