Chimera by Rob Thurman
published by New American Library in June 2010
Ten years ago, Stefan Korsak’s younger brother was kidnapped. No one knew who took Lukas, or why. He was simply gone. But not a day has passed that Stefan hasn’t thought about him. As a rising figure in the Russian Mafia, Stefan has finally found him.
But when he rescues Lukas, Stefan must confront a terrible truth – his brother is no longer his brother. He is a killer. Trained, brainwashed, and genetically transformed into a flesh-and-blood machine with only one purpose: assassination. Now those who created him will do anything to reclaim him.
As Stefan grows closer to his brother, he realizes that saving Lukas may be easier than surviving him...