A man and his wife go on holiday in the New Forest, where they find old ruins and among it, a tattered diary. Intrigued, they begin to read, and are drawn into the tale of a bereaving man from the 19th Century, who has visions of a green sun and creatures clambering from the well outside his house. Slowly, as madness takes him, these cosmic visions intensify and he finds himself under siege; his daughter, pet cat and his independence are under dire threat, leaving him alone, afraid, and at the mercy of horrific, otherworldly invaders. He witnesses alternate histories of the world, grim futures, and at the end of all, a dreadful predator patiently broods – hoping to sate its hunger. What fate awaits the Victorian man?
Will the diary reveal secrets best left in dust? And what is the ultimate purpose of the green sun, looming over the Earth like an emerald?