Our Country`s Good depicts the changing process of the desperate prisoners in an unexplored land, while they prepare to perform Recruting Officer, a British comedy from the 18th century. In this article, I try to show how a play could make changes among the prisoners in the deepest despair who participated in the first performance of the play in Australia. In the beginning, Timberlake Wertenbaker explains what the authorities think about theatre and why the Governor Philip supports the prisoners` performance so strongly. The most dramatic salvation takes place by the practical transitions of the participating prisoners and the officer, Ralph. Emotional alterations of the prisoners are reflected in the reversed structure of the play by placing the tone of ending in the first scene and plans for the future and even the prologue of the play within the play in the last. The personal changes through drama are described with concrete illustrations: activeness of the prisoners towards their lives, ambitions for the new lives in the unexplored territory, interests in the new love. The prisoners who don`t have any individuality at the beginning of the play show their diversity and then they become one to resist against the outside oppression for their performance. On the other hand, the play becomes an effective history class, where the writer portrays the arrival of The First Fleet with the founding fathers and mothers of Australia. Also explained are the historical facts about the first drama performance in Australian history, the conventions of comedy of manners in Britain, and the realities of lower class in the 18thcentury of Britain. The play doesn`t show any predominant hero or heroine but various characters have their voices on the same level and feelings and thoughts of diverse classes, gender and races are reflected in the play. Wertenbaker has demonstrated the firm belief in the power and the value of theater, that a piece of drama can change a man, and its effective history education can begin a new life for him/her, even when he/she is just in the deepest desperation.