I notice that you had associated your question with Ted Hughes' Shakespeare and the Goddess of Complete Being. However, you'll need to make this link more specifically obvious in your question, if, in fact, you would like to know something about how Much Ado relates to Ted Hughes' work. For now, I'll summarize what happens in Act III of Shakespeare's play.
In scene one, Hero, Margaret and Ursula trick Beatrice into believing that Benedick has confessed that he loves Beatrice. They say that Beatrice is too haughty, and so Benedick must love on in silence. And yet, Beatrice ends the scene alone onstage, confessing to the audience that she will "requite" Benedick's love.
In scene two, Leonato, Don Pedro and Claudio give Benedick a hard time because he is all clean-up and shaved, so he must be "in love." Benedick bears their antics and then asks to speak to Leonato alone (about asking for Beatrice's hand). Then, Don John enters and tells Claudio and Don Pedro that he will show them proof that Hero is unfaithful.
In scene three, the bumbling Dogberry, Verges and the Watch are introduced. These are comical "police" characters who, almost by accident, arrest Borachio after he confesses to Conrad the part he played in tricking Claudio and Don Pedro to believe that Hero was kissing him on her balcony. (He was there with Margaret, not Hero.)
In scene four, Hero, Margaret and Ursula tease Beatrice about her affection for Benedick as they prepare Hero for her wedding to Claudio.
In scene five, Dogberry and Verges try to alert Leonato as to the villainy that is afoot, yet he does not take them seriously and sends them away, as he is very busy getting ready for Hero's wedding. Dogberry and Verges, not to be deterred, plan to question and record the confession of Borachio themselves.
For more on scenes 1-3 of Act III of Much Ado About Nothing, please follow the links below.