Act Four, Scene One
The people are all gathered in the church to witness the wedding between Hero and Claudio. Leonato tells Friar Francis to hurry up. The Friar asks Claudio if he has come to marry Hero, to which Claudio replies, "No" (4.1.6). Leonato ignore the answer by playing with words to give it a different meaning, but Claudio interjects when asked if anyone knows why they should not be married. He tells Leonato, "Give not this rotten orange to your friend" (4.1.30) and accuses Hero of infidelity.
Don Pedro also refuses to defend Hero's honor, telling Leonato that he watched with his own eyes as Hero embraced another man the night before. Claudio cries out, "O Hero! What a Hero hadst thou been" (4.1.98) before once again saying farewell to her forever. "But fare thee well, most foul, most fair, farewell" (4.1.101).
Hero faints and falls to the ground. Don John, Don Pedro and Claudio all leave the church. Beatrice runs up and tries to help her cousin, but Leonato tells her that, "Death is the fairest cover for her shame" (4.1.113). Leonato then tells them that he is ashamed to have had such a daughter and that he wishes she had never been born. Benedick says, "Sir, sir, be patient. / For my part, I am so attired in wonder /I know not what to say" (4.1.142-144). Friar Francis tells them to stop attacking Hero. He tells them that by noting her complexion and the way she reacted, he has become convinced that she is actually guiltless.
Hero awakes and tells them that she has know idea what man Claudio thinks he saw her with. Leonato swears that if she is lying, he will hurt her, but if Claudio and Don Pedro maliciously harmed her honor then he will be avenged on them. Friar Francis tells Leonato to pretend that Hero has died of shame. He tells Leonato that if Hero pretends to be dead, instead of remembering her dishonor people will pity her and even Claudio will regret his words. Benedick promises to keep the secret as well, in spite of his intimacy with Claudio.
Everyone agrees to the plan and leaves. Only Benedick and Beatrice remain behind. They both declare their love for each other and Benedick asks her to make him do anything to affirm how much he loves her. Beatrice famously replies, "Kill Claudio" (4.1.287). Benedick at first says he will never do such a thing, and Beatrice tells him he does not really love her then. She tries to leave, but Benedick repents his answer and stops her. He tells her that he will challenge Claudio for her.
Act Four, Scene Two
Dogberry has brought Borachio and Conrad before the Town Clerk (the Sexton) and is interrogating them. Everything is carefully written down to avoid any mistakes. Dogberry is completely incompetent as an examiner, but the Sexton takes charge and orders the watchman who arrested them to step forward. He relates that he overheard them discussing the plot against Hero's reputation.
The sexton informs the men that they cannot deny the charge since Don John secretly stole away that morning. He further tells them that Hero was accused by Claudio in the church and died from humiliation. The men are bound and ordered to be taken to Leonato.
The fear of the men that they will be cuckolds is inherent in the scene where Claudio accuses Hero in the church. Leonato falsely thinks he has noted that she is guilty. Claudio further insults him by stating, "Give not this rotten orange to your friend" (4.1.30). Hero's fainting is taken as sign of her guilt, leading Leonato to tell Beatrice that, "Death is the fairest cover for her shame" (4.1.113). This is part of the social norms, it is Leonato's way of avoiding humiliation. Leonato chooses Hero's death in order to protect his reputation and avoid embarrassment.
Claudio now mimics the first time he thinks he has lost Hero. "But fare thee well, most foul, most fair, farewell" (4.1.101). This is virtually identical to 2.1.173. The audience by this point can tell that Claudio is a bad reader; after all, he makes the same mistake twice! He is also the most unfriendly lover in Shakespeare. Claudio dotes on Hero in his mind but prefers to choose male bonding over marriage. This becomes even more apparent in the next act when Claudio and Don Pedro mock Benedick together; Claudio shows no remorse for Hero's death and appears positively triumphant in having killed her.
It is interesting to note that Benedick becomes speechless when Hero is accused. Benedick says, "Sir, sir, be patient. / For my part, I am so attired in wonder / I know not what to say" (4.1.142-144). This marks the first time that he is unable to comment on the proceedings around him. For Benedick, it also moves him away from his male companions and his jocular talking and towards Beatrice, with whom he is more serious and less verbal.
Of all the men and women present at the wedding, only Friar Francis actually "notes" Hero. He says, "By noting of the lady...trust not my age...If this sweet lady lie not guiltless here" (4.1.157,166,168). The Friar is correct as we all know, and his choice of words, "by noting of the lady" is significant. It is the first time that anyone points out to the characters what we all know to be true; they fail to note what is happing around them.
Friar Francis is similar to Friar Laurence in Romeo and Juliet. He tries to save Hero by making her seem dead. "Come, lady, die to live" (4.1.253). This parallels the death of Juliet. The later marriage between Hero and Claudio will serve as a resurrection moment. Thus Friar Francis plays God with Hero's life and later resurrects her in a shroud of death.
One of the most significant lines is when Beatrice tells Benedick to "Kill Claudio" (4.1.287). She asks this as a way for Benedick to prove his love for her. Her demand essentially forces Benedick to choose between the brotherly love of men and the loyalty of a man to his wife. Beatrice knows that she must destroy Benedick's former male bonding. Her order is therefore a command for Benedick to support her against Claudio, and represents the only way for them to have a mature relationship.
Much Ado About Nothing is the only comedy in which no woman dresses as a man to influence the plot. Beatrice comes closest to this function, saying, "O God that I were a man! I would eat his heart in the market place" (4.1.303-304). She cannot take revenge on Claudio herself, indicating the power of the men in Messina. Beatrice therefore falls back on her wit to get Benedick to challenge Claudio.
For the first time sense is made out of the nonsense of the plot. This is done by the Sexton who cuts through Dogberry's nonsense. It is a crucial turning point in the play, akin to when Friar Francis notes Hero's innocence, because someone finally notes what is wrong and forces it to be clarified.