The purpose of this study is to analyze American playwright Thornton Wilder's one-act plays The Wreck on the Five-Twenty-Five (1957), Someone from Assisi (1961) and Childhood (1960). In the late 1950's Wilder turned his attention to the short play form and envisioned two cycles depicting The Seven Deadly Sins and The Seven Ages of Man for the arena stage of The Circle in the Square Theater, New York City's Greenwich Village, Off-Broadway. The plays Infancy, Childhood and Someone from Assisi premiered at Circle in the Square on January 11, 1962, as part of the evening called Plays for Bleecker Street: Plays in One Act for an Arena Stage, directed by its co-founder José Quintero. Although the season was a success, Wilder believed his plays needed many revisions. He never wrote the Sins cycle to his satisfaction; as for the Ages cycle, he delivered Infancy and Childhood, but Youth, The Rivers Under the Earth, A Ringing of Doorbells and In Shakespeare and the Bible were left unfinished. This study also comprises excerpts of the three original plays translated into Portuguese to show how Wilder worked in detail his stage directions and punctuation marks so that actors could convey their appropriate subtexts on stage. We will discuss the drama influences on Wilder´s theatre, the play in one act, the epic theatre and the way Wilder managed the concept of time in his plays. Wilder believed Off-Broadway productions were a good alternative to the expensive and business-oriented Broadway shows because they were economical, tickets were affordable, and playwrights could experience more independence.