Leviathan

Raven Spade and his son Evan ship and sell cargo throughout local star systems. For Raven, the life of a spacer is a front. He's a bounty hunter employed by the Federation Of Free Planets. For years, Spade has followed leads surrounding pirate attacks and rumors about the mysterious Eusian Empire. As the frequency and severity of attacks increases, Spade connects with his brother Gunnar and a scheme is hatched to track the pirates to their hidden base. However, nothing goes according to plan. An insider within the Federation is feeding the pirates information. Spade's ship is destroyed. A military warship is captured and falls into the hands of the pirates. Raven is presumed dead or guilty. Gunnar and Evan pick up the mission and soon learn a dark and terrible secret surrounding the pirates, Eusian slave labor, and find themselves in the belly of the beast.