Man's outer colonies are being destroyed one by one, leaving nothing behind. Suspecting an old enemy, Captain Henry Kuttner, of the Solar Navy rail-gun sip the Onslaught, wants to investigate.
But the Onslaught is scheduled to be decommissioned, and Captain Kuttner given mandatory retirement. But this old war dog isn't going down without a fight. Going against orders, Kuttner leads his crew in search of answers. That search leads straight into the territory of mankind's former enemies, the reptilian Draconi, whose colonies are also being destroyed, and they blame man.
Now the crew of the Onslaught must risk violating a fragile peace treaty and all-out war to solve a cosmic mystery before more lives are lost. Only the ship's maverick first officer and a disgraced Draconi scientist can unravel the secret of this enigmatic enemy before it's too late.
Meanwhile, in the outer dark, an ancient enemy returns. An enemy known only in the songs of a long-dead alien race. An enemy that leaves chaos in its wake.