According to this letter, Don Pedro of Aragon and his army are coming to Messina tonight.
Act 1 Scene 1
My dear Signior Leonato, hosting my whole army is such a huge burden.
Act 1 Scene 2
I heard that Prince Don Pedro likes Hero as he and Claudio were walking in an orchard
Summary: Leonato announces that Don Pedro is coming home from a long war
Act 1 Scene 2
Summary: Don Pedro returns home with Claudio, Benedick, Balthasar, and Don Jon the "Bastard"
Act 1 Scene 3
Summary: Leonato's elder brother, Antonio, tells him of a misheard conversation between Prince Don Pedro and Claudio and erroneously believes Don Pedro is in love with Hero. Antonio's servant overheard the conversation.
Act 1 Scene 3
Summary: Leonato decides to be careful and ensure that Hero really does like Don Pedro
I will not believe it until proven true
Summary: Don John is venting to Conrad that he
How come my brother, Don Pedro, receives so much success and fame and I don't?
Summary: Borachio arrives and tells Conrad and Don John that Don Pedro is planning to give Hero over to Claudio. This gives Don John some naughty ideas and they head out to the party
Don Pedro is planning to attend a feast to attract Hero's attention and give her to Claudio