Covering more than seven-tenths of Earth's surface, the planet's freshwater bodies and oceans together host a diversity of aquatic life. What kind of stars inhabit the seas? What makes whales lose their way? Get ready to meet an ocean 'unicorn', swim with dugongs and investigate some of the weirdest looking residents of the deep. From the serpent-like oarfish to the giant Pacific octopus, here is our sampling of creatures that captivate scientists and storytellers alike!