The play begins with the soldiers, Benedick, Claudio and Don Pedro, returning from the war. When they arrive at Leonato's house in Messina, Beatrice meets them and she and Benedick wittily banter back and forth. They appear to have known each other previously.
Claudio falls in love with Leonato's daughter, Hero on sight as both her looks and her nature appeal to him. Don Pedro offers to disguise himself as Claudio at a ball that evening to win Hero's hand for his friend.
Borachio overhears Claudio's declaration of love and reports back to Don John, the villain of the play. Don John plots to deceive Claudio.
The matchmaking plan for Hero and Claudio is a success and Leonato sets their wedding date for one week's time. Don Pedro has an idea to make Beatrice and Benedick fall in love as well.