Dragon Steel — Laurence Yep

In a fantastic undersea world, one princess fights to save her home.

Leaving behind the human world of Ramsgate, Princess Shimmer transforms herself back into her real dragon form and, with Thorn by her side, dives deep into the waters of an underground volcano--to seek help in restoring her once-gentle world of the Inland Sea. Because the evil Civet has stolen her sea home, Shimmer discovers that all surviving members of her clan have been enslaved by the High King and forced to temper dragon steel, deep within the sweltering volcano mines.

In a maze of coral caverns, guided by mist stones and breathing pearls, Shimmer and her companions Indigo and Thorn venture into danger-filled waters where neither friends nor foes are to be trusted. It is with a triumphant combination of magic and indomitable spirit that the princess avenges her claim--with a wisdom and power as great as dragon steel itself.