"The Book of Disquiet" is a posthumously published collection of thoughts and musings of a solitary dreamer, who is a Lisbon-based bookkeeper. The book delves into the mind of a man who is discontented with his mundane life and finds solace in dreaming and writing. The narrative is a profound reflection on life, solitude, and the nature of humanity, filled with philosophical insights and poetic language. The protagonist's introspective journey and his struggles with existential despair make it a seminal work in the genre of literary modernism.

This collection brings together the rich and varied poetic works of one of Portugal's most celebrated literary figures, a writer known for his multiple writing personas, or 'heteronyms.' The book showcases a selection of poems that delve into themes of existentialism, identity, and the nature of reality, reflecting the author's deep introspection and his fascination with the self and its multiplicities. The poems range from sonnets to free verse, each offering a window into the author's complex inner world and his philosophical musings, all while capturing the unique spirit of early 20th-century Portuguese culture.