Literary theoretician and Ackroyd scholar, Susana Onega resembles Peter Ackroyd’s historiographic metafictions to North American “fabulation” and Spanish-American “magic realism.” However, I have doubts as Peter Ackroyd’s novels cannot be termed any closer to ‘realism.’ Therefore, I would like to create a reference corpus consisting of the texts belonging to the former two sub-genres and calculate the similarities or distances between them and my primary corpus. In terms of Brown’s novels, I would like to study the lexical diversity in them and observe the changes, if they happened, with time – from his first novel to the last one. Before becoming a best-selling author, Dan Brown has already been publishing novels. Thus, I would like to explore if criticism of his writing style or his later books’ worldwide acknowledgment has caused any transformations in his texts.