John and Elizabeth Proctor are arguing. Elizabeth is still bitter about John's affair with Abigail, and he is angry that she won't forgive him. Tension is in the air, and into this tension walks Mary Warren, their servant.

When John sees Mary, he grabs her, furious that she has gone to Salem without his permission. Meanwhile, Mary pleads for mercy; her pallor suggests that she is not well. Mary tells John that she has been in court all day, but John demands to know when she will do the work that she's being paid for. In response, Mary tells Elizabeth that she made a doll for her while waiting for the proceedings to finish in court. She then cryptically tells Elizabeth that they must all love each other now.

Meanwhile, John demands to know whether it's true that fourteen women have been arrested. Mary replies that, in actuality, thirty-nine women have now been arrested on suspicion of witchcraft. She then breaks down in tears. Mary says that Goody Osburn has been sentenced to hang. Sarah Good, however, has been spared due to her confession that she made a pact with the devil.

Mary also claims that Goody Osburn sent a strange spirit over the court that day and is convinced that Goody Osburn has been trying to kill her. According to Mary, Goody Osburn has the power to strangle others without physically touching them. She also tells John and Elizabeth that the older woman likes to mumble whenever she is denied the items she has begged for. Goody Osburn refused to admit that her mumbles were curses. Instead, the older woman claimed that she was reciting the commandments. However, when the judge ordered her to recite the Ten Commandments, Goody Osburn could not do so.

Mary's smug account of events prompts John to forbid her to go to court again. For her part, Mary insists that she is carrying out important work by testifying. Both John and Elizabeth are aghast at her words, but Mary is convinced that confessions will save the accused women. Next, she reveals that Sarah Good is pregnant. Elizabeth is incredulous at this revelation. After all, Sarah is almost sixty.

Somehow, Mary is sure that Sarah won't be harmed, on account of the child. She informs John and Elizabeth that she, Mary, is now an official of the court and must be allowed to discharge her duties. John tries to whip Mary for her impertinence, but Mary screams that she will no longer tolerate being whipped by her employer. She then claims that she actually saved Elizabeth's life that very day.

Apparently, Elizabeth's name was brought up in court, but Mary testified that Elizabeth never showed evidence of demonic possession or a desire to hurt anyone. Because of Mary's testimony, the judges did not indict Elizabeth. Realizing that he has been painted into a corner, John tells Mary to go to bed. An argument ensues between the two, but Mary soon relents and leaves the room.

Elizabeth worries aloud that Abigail will find a way to incriminate her in court. She is convinced that it's no coincidence that her name came up in court; Abigail wants to get rid of her and take her place in the Proctor household. Elizabeth accuses John of still having feelings for Abigail, but John denies it. He tells her that his affair was born out of a moment's passion and that he never promised Abigail he would marry her. Still, Elizabeth tells John to break whatever promise he made Abigail. Her words increase John's frustration. He tells Elizabeth that, by her demands, she is making him a dishonest man (since he never made any promises of marriage to Abigail).

In response, Elizabeth accuses John of being reluctant to face the truth of his actions. She maintains that Abigail still has influence over John: "She has an arrow in you yet, John Proctor, and you know it well!" Their argument is interrupted by the appearance of Mr. Hale.