In Act 2 of The Crucible, where does John Proctor decide to go and what does he plan to do there?

John initially decides to go to the village to speak to Abigail Williams, their erstwhile maid, at his wife's insistence. The Proctors have just heard from their current maid, Mary Warren, who is now an official of the court as a witness in the trials, that someone had accused Elizabeth of witchcraft. She refuses to mention the accuser's name but Elizabeth suspects that it is Abigail. She asks John:

John, with so many in the jail, more than Cheever's help is needed now, I think. Would you favor me with this? Go to Abigail.

Elizabeth is afraid that Abigail wants her dead and she wishes John to break whatever attachment Abigail thinks she still has with him by calling her a whore:

Then go and tell her she's a whore. Whatever promise she may sense - break it, John, break it.

Elizabeth accuses John of being unwilling to go and he becomes angry, telling her that she should not begrudge him his anger and think him base. He tells her that his anger is justified since doing what Elizabeth demands speaks of deceit. He had never promised Abigail anything and gaver her only

The promise that a stallion gives a mare ... 

He believes that Elizabeth will always hold his adultery against him and that he will never be free of her suspicion.

Elizabeth then passionately cries out:

You'll tear it free - when you come to know that I will be your only wife, or no wife at all! She has an arrow in you yet, John Proctor, and you know it well!

At this point, Reverend Hale arrives and the argument ends. Later, Ezekiel Cheever and Marshal herrick arrive to serve a warrant of arrest on Elizabeth. They had been told that Elizabeth had used a poppet to harm Abigail, who had cried out at dinner that night. A needle was found stuck in her stomach and she accused Elizabeth of having used the doll to perform witchcraft. A poppet is found with a needle stuck in its belly and when Elizabeth hears that it was Abigail who had accused her she cries out:

Why - ! The girl is mur-der! She must be ripped out of the world!

This, to Cheever, is ample proof that Elizabeth wants to harm Abigail and he is ready to execute the warrant. John angrily tears it up but Elizabeth tells him that she will go with the officers. She is then arrested.

John then decides that he will go to court the next day to defend Elizabeth. he insists that Mary Warren should accompany him to give evidence of Abigail's deceit. Mary had been fashioning the doll whilst in court and Abigail was sitting next to her, witnessing how she stuck the needle into the doll's stomach for safekeeping. John also intends to tell the court that Abigail had told him their accusations had nothing to do with witchcraft. He wishes to prove that Abigail is a liar and a fraud.

It is tragic that John's efforts come to nothing for Abigail and the other girls soon overwhelm Mary Warren and she turns against him. Furthermore, his attempts at proving Abigail's malevolence are a failure since Elizabeth unknowingly lies to the court, thinking that she was saving her husband. John is arrested and later also accused of witchcraft. He is ultimately hanged.