As was noted in the preceding act, Mariane represents the simple, sweet, demure, and obedient daughter. In contrast, we see that the son represents the typical hot-tempered young man whose anger interferes with the trap being set for Tartuffe.
In this opening scene, Dorine is seen setting her plan into motion. As the wise and observant maid, she has noted that in the past Tartuffe seemed smitten with Elmire, and she now feels that Elmire might be able to persuade Tartuffe to reject the proposed marriage. Dorine, then, sets the plan in motion without having any idea that Tartuffe will later trap himself by his infatuation with Elmire. In other words, even though Dorine is responsible for beginning the revelation, not even she is aware of the exact nature of events about to occur.
When Damis hides in the closet to listen to the conversation between Elmire and Tartuffe, Molière is using one of the oldest devices in the theater; that is, the idea of having a person concealed and listening to some type of revelation. This same technique will become the method later by which Orgon is awakened to Tartuffe's hypocrisy.
