Grace knows there is something bad about the big metal shed at the back of the yard. She sees it in the way the animals keep away from the fumes, and her parent's growing obsession with the chemicals they create.
Grace is taken from her home late one night by her dad. They make a rushed exit with little explanation for their departure. Mom is not with them, and only quiet reassurance is given for her absence. Grace knows it's because of the shed and the promises she made to her mom over the past few months. She knows the secrets buried beneath the shed are slowly rising to the surface.
Grace is brought to a small, prairie town. Here, Grace must sift through the questions that have haunted her. She begins to unravel the mysteries of her parent's shed, her uncle's troubled past, and the terrible secret she promised her mother she'd keep. But the shed and its darkness have followed her to this new place, determined to make sure its secrets stay hidden no matter the cost.