The Doctor is on the trail of a sentient book entitled "a bestiary of legendary and magical creatures". The Doctor tracks the book to Earth where it begins creating mythical creatures such as a unicorn and a phoenix. The Doctor, with the help of a talking cat and a house-bound neighbour, manages to defeat the book as it creates a dragon from human and animal body parts. After the Doctor leaves in the TARDIS, a strange rash on the house-bound neighbour transforms into the Doctor, who quickly defeats the book's final creation before dissolving into nothingness.
- Thinking books work in the same manner as audiobooks, except they work with thought processes.
- The book creates a unicorn from toilet paper.
to be added