Septimus Warren Smith is a character from Virginia Woolf's novel, "Mrs. Dalloway." He is a World War I veteran who struggles with severe mental health issues, including post-traumatic stress disorder. His experiences in the war haunt him, leading to hallucinations and a disconnection from reality. Throughout the novel, Septimus's story intertwines with that of Clarissa Dalloway, the main character. His tragic journey highlights the impact of war on individuals and society, as well as the challenges of communication and understanding in a rapidly changing world. His character serves as a poignant commentary on the struggles of those affected by trauma.