Warner Bros. Pictures Animation is developing a film adaptation of Zac Gorman's middle-grade fantasy book series, "Thisby Thestoop," with screenwriters Steve Desmond and Michael Sherman attached to pen the script based on the first book, "Thisby Thestoop and the Black Mountain." The story follows a young heroine who is the gamekeeper of a vast, creature-filled dungeon, embarking on an adventure that combines fantasy, humor, and character-driven storytelling. Gorman, who previously worked on "Over the Garden Wall" and "Welcome to the Wayne," had his book series recognized as a 2018 Cybils Awards Finalist and a 2021 Washington Library Association Sasquatch Book Award Nominee. Desmond and Sherman are known for their work on adaptations like "Knock at the Cabin" and "Harry's All-Night Hamburgers," and have several other projects in development.