The Five Gold Bands (azw3,epub,mobi,pdf) - Jack Vance

When earthlings discover that the galaxy is teeming with advanced societies with the secrets of interstellar travel, one of them steals the technology, triggering a massive manhunt across the stars. HIDE-AND-GO-SEEK AMONG THE PLANETS Five bracelets of solid gold-five clues that began an interstellar treasure hunt. And as the luck of the Irish would have it, Paddy Blackthorn found himself the chief hunter-and the chief hunted. He had only the cryptic messages imprinted in the five armbands so involuntarily left him by the five planetary rulers. He had also the help of a little, black-haired Earther girl to figure out their secrets. But it was no children's game they were playing. Old Mother Earth, now abandoned by her spawn, foundered on the verge of extinction. Only the treasure Paddy sought would suffice to rescue the home planet-and incidentally to rule the rest of the cosmos.