Hunted — James Alan Gardner

For the children of Admiral Alexander York, perfection wasn't just expected, it was guaranteed--written into their DNA before they were born. But while Samantha grew into the physical and mental marvel their father had bought and paid for, her twin brother Edward proved a disappointment. Genetic tinkering had raised Sam above the common herd, but Edward's faultless body housed a faulty brain.

It took all the Admiral's influence to get Edward commissioned in the Outward Fleet Explorer Corps--a fiercely independent band of misfits who referred to themselves proudly as Expendables. Accompanying Sam on a mission to the troubled planet of Troyen, home to the alien Mandasar, Edward found himself in the midst of a civil war. There, in an instant of horrifying insanity, Sam was killed, along with the alien hive-queen.

For the next twenty years, Edward was exiled to a lonely outpost on one of Troyen's moons, blamed by the Admiral for Sam's death--and blaming himself as well. But when escalating violence forces the evacuation of the system, Edward embarks on a perilous journey home. that will lead him into a forgotten past--and, with the assistance of another ex-Expendable, the greatest Explorer of them all, the legendary Admiral Festina Ramos, into a future thick with conspiracy and betrayal. For there lurks a dark secret powerful enough to bury the hopes of human and Mandasar alike...or give them a new and brighter beginning.