Tennessee Williams is often referred to as one of 20th century Americas greatest playwrights, alongside the likes of Arthur Miller and Eugene ONeill. A staunch proponent of the realism movement, Williams is known for his enduring characters and their tragic stories. His contribution to the tumultuous literary climate of the 1940s with his distinctive, brutally honest, and emotionally complex voice, makes his work a riveting basis for research and analysis. This thesis explores the moral vision of Williams through the deceptive practices of his dramatic characters. Though illusion may be effective in disguising the bare ugliness of man, Williams emphasises the importance of mustering the courage to confront the truth, no matter what the situation. The struggle to accept truth as a necessary path to salvation is explored through the characters of three of his most iconic plays. The paper will attempt a cross-referential study amongst three of Tennessee Williams most acclaimed works Cat on a Hot Tin Roof (1955), A Streetcar Named Desire (1947), and The Glass Menagerie (1944) and will analyse and compare the presentation of mendacity, self-deception, and subterfuge through the contextual and historical factors that influenced the playwright, the nature of the characters, as well as his interpretation of the literary movements of social realism and existentialism.