When his crew expresses doubts about the existence of the octo-shark, a creature that is half octopus and half shark, Captain Banana Beard of the Nearly Fearless Monkey Pirates and his crew set out on a hunt to find the mythical monster--but the search nearly turns all of them into an octo-shark lunch.

"Things can't get any worse. Legends are running riot. Half-Hunters are out of control. Darkmouth has been taken away from Finn and Emmie. And Finn's dad, Hugo--proud Legend Hunter-- is washing dogs for a living. But something even more terrifying lurks beneath the surface: an ancient horror threatening both our world and the Infested Side. So scratch that. Things can get worse. Much worse"--Inside dust jacket.

"Welcome to Tiankawi - shining pearl of human civilization and a safe haven for those fleeing civil unrest. Or at least, that's how it first appears. But in the semi-flooded city, humans are, quite literally, on top: peering down from shining towers and aerial walkways on the fathomfolk - sirens, seawitches, kelpies and kappas - who live in the polluted waters below. For half-siren Mira, promotion to captain of the border guard means an opportunity...