It has been centuries since the oceans rose and swallowed up all the nations of men. Now only beasts and unseen horrors lurk below the waves, kept in check by one man: Captain Nemo, in his legendary ship the Nautilus. Until one day, young Arona comes onboard his ship, a stowaway from times long past, giving Nemo his first crew member in years. But as he raises the young orphan in his image, she begins to have questions that ask Nemo to dredge up the past: what has become of the world? Can it be saved? And was it all worth it?