Mood Spectrum in Graham Greene examines the pathology of bipolar disorder through symptoms uniquely expressed in the writer's novels. It explains and illustrates how mutated genes endow him with artistic genius, even as they engender a mental illness that too often results in a life barren of intimacy, and in an unquiet mind that can lead to psychosis and suicide if untreated. Critics have generally either ignored his illness in his novels or ascribed agency based on false psychological models, despite Greene often projecting his illness into character-constructs that share his condition and that provide the reader with a virtual case study of manic depression.