"The Hollow" is a trade paperback book by Nora Roberts, part of the Sign of Seven Trilogy series published by Penguin Publishing Group in 2019. The novel falls under the genres of fiction, with elements of occult and supernatural themes, contemporary and paranormal romance, as well as suspense. With a total of 336 pages, this English-language book is designed with dimensions of 8.2 inches in length, 5.5 inches in width, and 0.9 inches in height, weighing 10.4 ounces.