Young Adult.

"Cassie Sullivan, the survivor of an alien invasion, must rescue her young brother from the enemy with help from a boy who may be one of them"--Provided by publisher.

I. The last historian -- II. Wonderland -- III. Silencer -- IV. Mayfly -- V. The winnowing -- VI. The human clay -- VII. The heart to kill -- VIII. The spirit of vengeance -- IX. A flower to the rain -- X. A thousand ways -- XI. The infinite sea -- XII. Because of Kistner -- XIII. The black hole.