Eleven-year-old Davey McCrary dreams of another life, one free from his alcoholic father's abuse and the daily torment he suffers from middle school bullies. He finds solace in his mother's old mythology book, especially the chapter about mermaids. The picture looks like his mom. If only he could see her again. Dreams become reality when Davey hears her call from the abandoned lighthouse, the same structure she leapt from to end her life. After seeing his mother's image within the waters from atop the lighthouse, Davey jumps in hopes of joining her, only to enter another world called The Nether where he meets the same fantastical creatures - the mermaid and the kraken - he read about in the mythology book. He must assume the mantle of The Lighthouse Keeper and cross the Endless Ocean to battle the one being who would see the destruction of both worlds, an enigma called the Dark Guardian. But as he sails across the golden waters, he realizes his father's shadow looms large over his passage. Now, he must confront his greatest fears or condemn the world around him to fall under the Dark Guardian's power.