Pirates of the Thunder: The Rings of the Master, Book 2

Hawks had refused to help the ambitious Lazlo Chen in his quest to find the five gold rings that could break Master System's hold over humankind -- and that refusal had landed him on the deadly prison planet Melchior. But when Hawks and some fellow prisoners engineered a bold escape, it seemed almost too easy. Hawks guessed that Chen was pulling the strings, but he couldn't shake the feeling that there was another, greater power involved. And that scared him. Now the stakes were rising, and Hawks was more determined than ever to find the gold rings. But Master System was out to capture him, and Chen was trying to follow him -- and the only place his small band of rebels could hide was smack in the middle of pirate territory...