The Rosetta Codex - Richard Paul Russo

Six-year-old Cale's first experiences of primitive Conrad's World were violent and tragic. Cale's wealthy father was killed in space on a business venture, leaving a lone shuttle to make landfall in the desert. Cale's guardian Sidonie was attacked as she lay dying after the crash, leaving Cale to be brought up alone among exiles and criminals.

Ten years later, Cale flees to the capital Morningstar and there joins the radical Resurrectionists - like him they believe the city was built on an ancient alien civilisation. His fortunes change rapidly when he meets the scarred Sidonie, his protector from birth, who reunites him with his family and fortune.

But Cale is driven to find an alien 'gateway' discussed in an old text, and is prepared to use all his new-found fortune to do so ... even at the cost of enraging his new family, and tracked every step of the way by the sinister Blackburn and his Sarakeen.