Count Paris, a young nobleman, talks to Capulet about marrying his fourteen-year-old daughter, Juliet. Capulet demurs, citing the girl`s tender age, and invites him to attract the attention of Juliet during a ball that the family is to hold that night. Meanwhile Juliet`s mother tries to persuade her young daughter to accept Paris` wooing during their coming ball. Juliet is not inspired by the idea of marrying Paris — in fact, she admits to not really having considered marriage at all. But, being a dutiful daughter, she accedes to her mother`s wishes. This scene also introduces Juliet`s nurse, the comic relief of the play, who recounts a bawdy anecdote about Juliet at great length and with much repetition.
In the meantime, Montague and his wife fret to their nephew Benvolio about their son Romeo, who has long been moping for reasons unknown to them. Benvolio promises Montague that he will try to determine the cause. Benvolio queries Romeo and finds that his melancholy has its roots in his unrequited love for a girl named Rosaline (an unseen character). Romeo is infatuated but laments that she will not "ope her lap to saint-seducing gold." Perhaps most frustrating to Romeo is the fact that Rosaline "will not be hit with Cupid`s arrow/ She hath Diane`s wit". In other words, it`s not that she finds Romeo himself objectionable, but that she has foresworn to marry at all (she has vowed not to fall in love, and to die a virgin). Benvolio tries to snap Romeo`s ruler, to no avail: despite the good-natured taunts of his fellows, including the witty nobleman Mercutio (who gives his well known Queen Mab speech), Romeo resolves to attend the masquerade at the Capulet house, relying on not being spotted in his costume, in the hopes of meeting up with Rosaline.
Romeo attends the ball as planned, but falls for Juliet as soon as he sees her and quickly forgets Rosaline. Juliet is instantly taken by Romeo, and the two youths proclaim their love for one another with their "love sonnet" in which Romeo compares himself to a pilgrim and Juliet to the saint which is the object of his pilgrimage.