Within the Blackhope Tower is a magical labyrinth, mysteriously appearing skeletons, and an ancient painting. For centuries, rumors milled around the Mariner's Chamber, which contained the labyrinth and famous painting. Sunni, her friend Blaise, and her stepbrother, Dean, visit the tower for a school project. But when Sunni sees her stepbrother disappear, seemingly inside the painting, she goes in search of him. In the desperate search for her stepbrother, Sunni encounters dangers unlike any other. She comes face-to-face with people who vanished in the painting centuries before.