The story of Under the Nine Suns takes place within the Sea of Clouds, a vast airy expanse in which continent sized pieces of land hang suspended like islands.  Cities and nations grow on the surface of these land masses called 'bergs.'  People travel back and forth in flying ships known as cloud cruisers, bringing trade, conflict and political intrigue. 

It is on the berg named Elarin that Kalrin Vallis, Kal to his friends, makes his home.  As an agent for the ardent Aleph Association, Kal must protect its members from assassination, supernatural creatures and mechanical nightmares, all while juggling the safety of his friends, family and morals.  All is not well on Elarin as Kal becomes increasingly aware of conspiracies and corruption that threaten to bring destruction and chaos in their wake.