Jean Paul Sartre wrote Huis Clos with the intent to create a world and develop characters that models his Existentialist beliefs. One of the main underlying themes of the play was the concept of "mauvaise foi (bad faith)," or the theory that with absolute freedom comes the responsibility one must have to oneself. If one abuses his freedom (of choice) and is not faithful to his heart and the knowledge that all his actions have consequences, Sartre states that he has bad faith. Furthermore, a person who allows others to influence their decisions so that they are no longer true to their own ideals qualifies as bad faith. Using all three characters as examples, Sartre portrays bad faith on three different levels - and allows their flaws to distinguish the conceptual variations of "le mauvaise foi."

Estelle could perhaps be seen as Sartre's main example of bad faith...