The Boy Who Came In From the Cold and Anything Could Happen by B.G. Thomas.
Series
The Center
Jack and Leo are teenaged operatives working for a shadowy organization known only as The Center, where Jack has lived since the age of three, under the supervision of a man he knows only as his guardian. Expected to complete dangerous assignments, Jack is a specialized agent with extensive training in covert techniques and martial arts. With each mission, Jack assumes a new identity, and with each mission he comes a little closer to figuring out who he is and why he’s at The Center.
The Dragon-ghosts of Viscaya Series by Jack Byrne.
The Dragon-ghosts of Viscaya Universe by Jack Byrne.
The General and the Horse-Lord by Sarah Black.
