Abigail begins to execute her plan against Elizabeth in Scene 4. At this point Abigail exercises all of the power she has gained from the beginning of the play. Abigail realizes that in order to have Elizabeth arrested, she will have to create tangible evidence for the court, because it dismissed her verbal accusation. She is prepared to do anything to charge Elizabeth with witchcraft.
Abigail realizes that she can use Mary Warren as a tool to incriminate Elizabeth, and so she constructs a plot based upon deception and manipulation of Mary Warren. Abigail has seen Mary Warren sewing the poppet in court and she knows that Mary Warren will give the doll to Elizabeth later. The fact that Abigail willingly inflicts a stabbing wound upon herself demonstrates how far she will go to destroy Elizabeth and possess Proctor.
Scene 4 also provides Proctor with an opportunity to discredit Abigail and prove the falsity of her accusation against Elizabeth. The problem is whether or not Mary Warren will testify against Abigail in open court. She admits that the poppet is her own and that Abigail saw her sewing it, and had even seen her store the needle inside. However, Mary Warren would not reveal this if Hale questioned her in order to disprove Abigail's claim. To save Elizabeth, Mary Warren must give up her sense of belonging, and face Abigail's initial threat of violence from Act I, Scene 2.
Mary Warren's fear of reprisal foreshadows Abigail's behavior toward Mary Warren in Act III. In addition, Mary Warren warns Proctor that Abigail will accuse him of adultery. This foreshadows the end of the play when Proctor reveals the affair in court.
